Colon and Rectal

A breakthrough in medical testing now allows for colorectal cancer screening with just a simple blood test, promising a more accessible and less invasive way to catch the disease early. 

The FDA on July 29 approved the test, called Shield, which can accurately detect tumors in the colon or rectum about 87% of the time when the cancer is in treatable early stages. The approval was announced July 29 by the test’s maker, Guardant Health, and comes just months after promising clinical trial results were published in The New England Journal of Medicine.

Colorectal cancer is among the most common types of cancer diagnosed in the United States each year, along with being one of the leading causes of cancer deaths. The condition is treatable in early stages, but about 1 in 3 people don’t stay up to date on regular screenings, which should begin at age 45.

The simplicity of a blood test could make it more likely for people to be screened for and, ultimately, survive the disease. Other primary screening options include feces-based tests or colonoscopy. The 5-year survival rate for colorectal cancer is 64%.

While highly accurate at detecting DNA shed by tumors during treatable stages of colorectal cancer, the Shield test was not as effective at detecting precancerous areas of tissue, which are typically removed after being detected.

In its news release, Guardant Health officials said they anticipate the test to be covered under Medicare. The out-of-pocket cost for people whose insurance does not cover the test has not yet been announced. The test is expected to be available by next week, The New York Times reported.

If someone’s Shield test comes back positive, the person would then get more tests to confirm the result. Shield was shown in trials to have a 10% false positive rate.

“I was in for a routine physical, and my doctor asked when I had my last colonoscopy,” said John Gormly, a 77-year-old business executive in Newport Beach, California, according to a Guardant Health news release. “I said it’s been a long time, so he offered to give me the Shield blood test. A few days later, the result came back positive, so he referred me for a colonoscopy. It turned out I had stage II colon cancer. The tumor was removed, and I recovered very quickly. Thank God I had taken that blood test.”
 

A version of this article appeared on WebMD.com.

A breakthrough in medical testing now allows for colorectal cancer screening with just a simple blood test, promising a more accessible and less invasive way to catch the disease early. 

The FDA on July 29 approved the test, called Shield, which can accurately detect tumors in the colon or rectum about 87% of the time when the cancer is in treatable early stages. The approval was announced July 29 by the test’s maker, Guardant Health, and comes just months after promising clinical trial results were published in The New England Journal of Medicine.

Colorectal cancer is among the most common types of cancer diagnosed in the United States each year, along with being one of the leading causes of cancer deaths. The condition is treatable in early stages, but about 1 in 3 people don’t stay up to date on regular screenings, which should begin at age 45.

The simplicity of a blood test could make it more likely for people to be screened for and, ultimately, survive the disease. Other primary screening options include feces-based tests or colonoscopy. The 5-year survival rate for colorectal cancer is 64%.

While highly accurate at detecting DNA shed by tumors during treatable stages of colorectal cancer, the Shield test was not as effective at detecting precancerous areas of tissue, which are typically removed after being detected.

In its news release, Guardant Health officials said they anticipate the test to be covered under Medicare. The out-of-pocket cost for people whose insurance does not cover the test has not yet been announced. The test is expected to be available by next week, The New York Times reported.

If someone’s Shield test comes back positive, the person would then get more tests to confirm the result. Shield was shown in trials to have a 10% false positive rate.

“I was in for a routine physical, and my doctor asked when I had my last colonoscopy,” said John Gormly, a 77-year-old business executive in Newport Beach, California, according to a Guardant Health news release. “I said it’s been a long time, so he offered to give me the Shield blood test. A few days later, the result came back positive, so he referred me for a colonoscopy. It turned out I had stage II colon cancer. The tumor was removed, and I recovered very quickly. Thank God I had taken that blood test.”
 

A version of this article appeared on WebMD.com.

A breakthrough in medical testing now allows for colorectal cancer screening with just a simple blood test, promising a more accessible and less invasive way to catch the disease early. 

The FDA on July 29 approved the test, called Shield, which can accurately detect tumors in the colon or rectum about 87% of the time when the cancer is in treatable early stages. The approval was announced July 29 by the test’s maker, Guardant Health, and comes just months after promising clinical trial results were published in The New England Journal of Medicine.

Colorectal cancer is among the most common types of cancer diagnosed in the United States each year, along with being one of the leading causes of cancer deaths. The condition is treatable in early stages, but about 1 in 3 people don’t stay up to date on regular screenings, which should begin at age 45.

The simplicity of a blood test could make it more likely for people to be screened for and, ultimately, survive the disease. Other primary screening options include feces-based tests or colonoscopy. The 5-year survival rate for colorectal cancer is 64%.

While highly accurate at detecting DNA shed by tumors during treatable stages of colorectal cancer, the Shield test was not as effective at detecting precancerous areas of tissue, which are typically removed after being detected.

In its news release, Guardant Health officials said they anticipate the test to be covered under Medicare. The out-of-pocket cost for people whose insurance does not cover the test has not yet been announced. The test is expected to be available by next week, The New York Times reported.

If someone’s Shield test comes back positive, the person would then get more tests to confirm the result. Shield was shown in trials to have a 10% false positive rate.

“I was in for a routine physical, and my doctor asked when I had my last colonoscopy,” said John Gormly, a 77-year-old business executive in Newport Beach, California, according to a Guardant Health news release. “I said it’s been a long time, so he offered to give me the Shield blood test. A few days later, the result came back positive, so he referred me for a colonoscopy. It turned out I had stage II colon cancer. The tumor was removed, and I recovered very quickly. Thank God I had taken that blood test.”
 

A version of this article appeared on WebMD.com.

WASHINGTON — A risk-stratified upper age limit may be beneficial for colorectal cancer (CRC) screening among patients who are ages 75 and older, according to a study presented at the annual Digestive Disease Week^® (DDW).

In particular, interval CRC risk can vary substantially based on the fecal hemoglobin (f-Hb) concentration in the patient’s last fecal immunochemical test (FIT), as well as the number of prior screening rounds.

“Less is known about what happens after the upper age limit has been reached and individuals are not invited to participate in more screening rounds. This is important as life expectancy is increasing, and it is increasingly important to consider the most efficient way of screening the elderly,” said lead author Brenda van Stigt, a PhD candidate focused on cancer screening at Erasmus University Medical Center in Rotterdam, the Netherlands.

In the Netherlands, adults between ages 55 and 75 are invited to participate in stool-based CRC screening every 2 years. Based on a fecal immunochemical testing (FIT) threshold of 47 μg Hb/g, those who test positive are referred to colonoscopy, and those who test negative are invited to participate again after a 2-year period.

FIT can play a major role in risk stratification, Ms. van Stigt noted, along with other factors that influence CRC risk, such as age, sex, and CRC screening history. Although this is documented for ages 55-75, she and colleagues wanted to know more about what happens after age 75.

Ms. Van Stigt and colleagues conducted a population-based study by analyzing Dutch national cancer registry data and FIT results around the final screening at age 75, looking at those who were diagnosed with CRC within 24 months of their last negative FIT. The researchers assessed interval CRC risk and cancer stage, accounting for sex, last f-Hb concentration, and the number of screening rounds.

Among 305,761 people with a complete 24-month follow-up after a negative FIT, 661 patients were diagnosed with interval CRC, indicating an overall interval CRC risk of 21.6 per 10,000 individuals with a negative FIT. There were no significant differences by sex.

However, there were differences by screening rounds, with those who had participated in three or four screening rounds having a lower risk than those who participated only once (HR, .49).

In addition, those with detectable f-Hb (>0 μg Hb/g) in their last screening round had a much higher interval CRC risk (HR, 4.87), at 65.8 per 10,000 negative FITs, compared with 13.8 per 10,000 among those without detectable f-Hb. Interval CRC risk also increased over time for those with detectable f-Hb.

About 15% of the total population had detectable f-Hb, whereas 46% of those with interval CRC had detectable f-Hb, Ms. van Stigt said, meaning that nearly half of patients who were diagnosed with interval CRC already had detectable f-Hb in their prior FIT.

In a survival analysis, there was no association between interval CRC risk and sex. However, those who participated in three or four screening rounds were half as likely to be diagnosed than those who participated once or twice, and those with detectable f-Hb were five times as likely to be diagnosed.

For late-stage CRC, there was no association with sex or the number of screening rounds. Detectable f-Hb was associated with not only a higher risk of interval CRC but also a late-stage diagnosis.

“These findings indicate that one uniform age to stop screening is suboptimal,” Ms. van Stigt said. “Personalized screening strategies should, therefore, also ideally incorporate a risk-stratified age to stop screening.”

The US Preventive Services Task Force recommends that clinicians personalize screening for ages 76-85, accounting for overall health, prior screening history, and patient preferences.

“But we have no clear guidance on how to quantify or weigh these factors. This interesting study highlights how one of these factors (prior screening history) and fecal hemoglobin level (an emerging factor) are powerful stratifiers of subsequent colorectal cancer risk,” said Sameer D. Saini, MD, AGAF, director and research investigator at the VA Ann Arbor Healthcare System’s Center for Clinical Management Research. Dr. Saini wasn’t involved with the study.

At the clinical level, Dr. Saini said, sophisticated modeling is needed to understand the interaction with competing risks and identify the optimal screening strategies for patients at varying levels of cancer risk and life expectancy. Models could also help to quantify the population benefits and cost-effectiveness of personalized screening.

“Finally, it is important to note that, in many health systems, access to quantitative FIT may be limited,” he said. “These data may be less informative if colonoscopy is the primary mode of screening.”

Ms. van Stigt and Dr. Saini reported no relevant disclosures.

WASHINGTON — A risk-stratified upper age limit may be beneficial for colorectal cancer (CRC) screening among patients who are ages 75 and older, according to a study presented at the annual Digestive Disease Week^® (DDW).

In particular, interval CRC risk can vary substantially based on the fecal hemoglobin (f-Hb) concentration in the patient’s last fecal immunochemical test (FIT), as well as the number of prior screening rounds.

“Less is known about what happens after the upper age limit has been reached and individuals are not invited to participate in more screening rounds. This is important as life expectancy is increasing, and it is increasingly important to consider the most efficient way of screening the elderly,” said lead author Brenda van Stigt, a PhD candidate focused on cancer screening at Erasmus University Medical Center in Rotterdam, the Netherlands.

In the Netherlands, adults between ages 55 and 75 are invited to participate in stool-based CRC screening every 2 years. Based on a fecal immunochemical testing (FIT) threshold of 47 μg Hb/g, those who test positive are referred to colonoscopy, and those who test negative are invited to participate again after a 2-year period.

FIT can play a major role in risk stratification, Ms. van Stigt noted, along with other factors that influence CRC risk, such as age, sex, and CRC screening history. Although this is documented for ages 55-75, she and colleagues wanted to know more about what happens after age 75.

Ms. Van Stigt and colleagues conducted a population-based study by analyzing Dutch national cancer registry data and FIT results around the final screening at age 75, looking at those who were diagnosed with CRC within 24 months of their last negative FIT. The researchers assessed interval CRC risk and cancer stage, accounting for sex, last f-Hb concentration, and the number of screening rounds.

Among 305,761 people with a complete 24-month follow-up after a negative FIT, 661 patients were diagnosed with interval CRC, indicating an overall interval CRC risk of 21.6 per 10,000 individuals with a negative FIT. There were no significant differences by sex.

However, there were differences by screening rounds, with those who had participated in three or four screening rounds having a lower risk than those who participated only once (HR, .49).

In addition, those with detectable f-Hb (>0 μg Hb/g) in their last screening round had a much higher interval CRC risk (HR, 4.87), at 65.8 per 10,000 negative FITs, compared with 13.8 per 10,000 among those without detectable f-Hb. Interval CRC risk also increased over time for those with detectable f-Hb.

About 15% of the total population had detectable f-Hb, whereas 46% of those with interval CRC had detectable f-Hb, Ms. van Stigt said, meaning that nearly half of patients who were diagnosed with interval CRC already had detectable f-Hb in their prior FIT.

In a survival analysis, there was no association between interval CRC risk and sex. However, those who participated in three or four screening rounds were half as likely to be diagnosed than those who participated once or twice, and those with detectable f-Hb were five times as likely to be diagnosed.

For late-stage CRC, there was no association with sex or the number of screening rounds. Detectable f-Hb was associated with not only a higher risk of interval CRC but also a late-stage diagnosis.

“These findings indicate that one uniform age to stop screening is suboptimal,” Ms. van Stigt said. “Personalized screening strategies should, therefore, also ideally incorporate a risk-stratified age to stop screening.”

The US Preventive Services Task Force recommends that clinicians personalize screening for ages 76-85, accounting for overall health, prior screening history, and patient preferences.

“But we have no clear guidance on how to quantify or weigh these factors. This interesting study highlights how one of these factors (prior screening history) and fecal hemoglobin level (an emerging factor) are powerful stratifiers of subsequent colorectal cancer risk,” said Sameer D. Saini, MD, AGAF, director and research investigator at the VA Ann Arbor Healthcare System’s Center for Clinical Management Research. Dr. Saini wasn’t involved with the study.

At the clinical level, Dr. Saini said, sophisticated modeling is needed to understand the interaction with competing risks and identify the optimal screening strategies for patients at varying levels of cancer risk and life expectancy. Models could also help to quantify the population benefits and cost-effectiveness of personalized screening.

“Finally, it is important to note that, in many health systems, access to quantitative FIT may be limited,” he said. “These data may be less informative if colonoscopy is the primary mode of screening.”

Ms. van Stigt and Dr. Saini reported no relevant disclosures.

WASHINGTON — A risk-stratified upper age limit may be beneficial for colorectal cancer (CRC) screening among patients who are ages 75 and older, according to a study presented at the annual Digestive Disease Week^® (DDW).

In particular, interval CRC risk can vary substantially based on the fecal hemoglobin (f-Hb) concentration in the patient’s last fecal immunochemical test (FIT), as well as the number of prior screening rounds.

“Less is known about what happens after the upper age limit has been reached and individuals are not invited to participate in more screening rounds. This is important as life expectancy is increasing, and it is increasingly important to consider the most efficient way of screening the elderly,” said lead author Brenda van Stigt, a PhD candidate focused on cancer screening at Erasmus University Medical Center in Rotterdam, the Netherlands.

In the Netherlands, adults between ages 55 and 75 are invited to participate in stool-based CRC screening every 2 years. Based on a fecal immunochemical testing (FIT) threshold of 47 μg Hb/g, those who test positive are referred to colonoscopy, and those who test negative are invited to participate again after a 2-year period.

FIT can play a major role in risk stratification, Ms. van Stigt noted, along with other factors that influence CRC risk, such as age, sex, and CRC screening history. Although this is documented for ages 55-75, she and colleagues wanted to know more about what happens after age 75.

Ms. Van Stigt and colleagues conducted a population-based study by analyzing Dutch national cancer registry data and FIT results around the final screening at age 75, looking at those who were diagnosed with CRC within 24 months of their last negative FIT. The researchers assessed interval CRC risk and cancer stage, accounting for sex, last f-Hb concentration, and the number of screening rounds.

Among 305,761 people with a complete 24-month follow-up after a negative FIT, 661 patients were diagnosed with interval CRC, indicating an overall interval CRC risk of 21.6 per 10,000 individuals with a negative FIT. There were no significant differences by sex.

However, there were differences by screening rounds, with those who had participated in three or four screening rounds having a lower risk than those who participated only once (HR, .49).

In addition, those with detectable f-Hb (>0 μg Hb/g) in their last screening round had a much higher interval CRC risk (HR, 4.87), at 65.8 per 10,000 negative FITs, compared with 13.8 per 10,000 among those without detectable f-Hb. Interval CRC risk also increased over time for those with detectable f-Hb.

About 15% of the total population had detectable f-Hb, whereas 46% of those with interval CRC had detectable f-Hb, Ms. van Stigt said, meaning that nearly half of patients who were diagnosed with interval CRC already had detectable f-Hb in their prior FIT.

In a survival analysis, there was no association between interval CRC risk and sex. However, those who participated in three or four screening rounds were half as likely to be diagnosed than those who participated once or twice, and those with detectable f-Hb were five times as likely to be diagnosed.

For late-stage CRC, there was no association with sex or the number of screening rounds. Detectable f-Hb was associated with not only a higher risk of interval CRC but also a late-stage diagnosis.

“These findings indicate that one uniform age to stop screening is suboptimal,” Ms. van Stigt said. “Personalized screening strategies should, therefore, also ideally incorporate a risk-stratified age to stop screening.”

The US Preventive Services Task Force recommends that clinicians personalize screening for ages 76-85, accounting for overall health, prior screening history, and patient preferences.

“But we have no clear guidance on how to quantify or weigh these factors. This interesting study highlights how one of these factors (prior screening history) and fecal hemoglobin level (an emerging factor) are powerful stratifiers of subsequent colorectal cancer risk,” said Sameer D. Saini, MD, AGAF, director and research investigator at the VA Ann Arbor Healthcare System’s Center for Clinical Management Research. Dr. Saini wasn’t involved with the study.

At the clinical level, Dr. Saini said, sophisticated modeling is needed to understand the interaction with competing risks and identify the optimal screening strategies for patients at varying levels of cancer risk and life expectancy. Models could also help to quantify the population benefits and cost-effectiveness of personalized screening.

“Finally, it is important to note that, in many health systems, access to quantitative FIT may be limited,” he said. “These data may be less informative if colonoscopy is the primary mode of screening.”

Ms. van Stigt and Dr. Saini reported no relevant disclosures.

TOPLINE:

For patients with gastric cancer, extending regular follow-up beyond the typical 5 years after gastrectomy was associated with improved overall and post-recurrence survival rates, new data from a retrospective analysis showed.

METHODOLOGY:

• Currently, postgastrectomy cancer surveillance typically lasts 5 years, although some centers now monitor patients beyond this point.
• To investigate the potential benefit of extended surveillance, researchers used Korean National Health Insurance claims data to identify 40,468 patients with gastric cancer who were disease free 5 years after gastrectomy — 14,294 received extended regular follow-up visits and 26,174 did not.
• The extended regular follow-up group was defined as having endoscopy or abdominopelvic CT between 2 months and 2 years before diagnosis of late recurrence or gastric remnant cancer and having two or more examinations between 5.5 and 8.5 years after gastrectomy. Late recurrence was a recurrence diagnosed 5 years after gastrectomy.
• Researchers used Cox proportional hazards regression to evaluate the independent association between follow-up and overall and postrecurrence survival rates.

TAKEAWAY:

• Overall, 5 years postgastrectomy, the incidence of late recurrence or gastric remnant cancer was 7.8% — 4.0% between 5 and 10 years (1610 of 40,468 patients) and 9.4% after 10 years (1528 of 16,287 patients).
• Regular follow-up beyond 5 years was associated with a significant reduction in overall mortality — from 49.4% to 36.9% at 15 years (P < .001). Overall survival after late recurrence or gastric remnant cancer also improved significantly with extended regular follow-up, with the 5-year postrecurrence survival rate increasing from 32.7% to 71.1% (P < .001).
• The combination of endoscopy and abdominopelvic CT provided the highest 5-year postrecurrence survival rate (74.5%), compared with endoscopy alone (54.5%) or CT alone (47.1%).
• A time interval of more than 2 years between a previous endoscopy or abdominopelvic CT and diagnosis of late recurrence or gastric remnant cancer significantly decreased postrecurrence survival (hazard ratio [HR], 1.72 for endoscopy and HR, 1.48 for abdominopelvic CT).

IN PRACTICE:

“These findings suggest that extended regular follow-up after 5 years post gastrectomy should be implemented clinically and that current practice and value of follow-up protocols in postoperative care of patients with gastric cancer be reconsidered,” the authors concluded.

The authors of an accompanying commentary cautioned that, while the study “successfully establishes groundwork for extending surveillance of gastric cancer in high-risk populations, more work is needed to strategically identify those who would benefit most from extended surveillance.”
 

SOURCE:

The study, with first author Ju-Hee Lee, MD, PhD, Department of Surgery, Hanyang University College of Medicine, Seoul, South Korea, and accompanying commentary were published online on June 18 in JAMA Surgery.

LIMITATIONS:

Recurrent cancer and gastric remnant cancer could not be distinguished from each other because clinical records were not analyzed. The claims database lacked detailed clinical information on individual patients, including cancer stages, and a separate analysis of tumor markers could not be performed.

DISCLOSURES:

The study was funded by a grant from the Korean Gastric Cancer Association. The study authors and commentary authors reported no conflicts of interest.

A version of this article appeared on Medscape.com.

TOPLINE:

For patients with gastric cancer, extending regular follow-up beyond the typical 5 years after gastrectomy was associated with improved overall and post-recurrence survival rates, new data from a retrospective analysis showed.

METHODOLOGY:

• Currently, postgastrectomy cancer surveillance typically lasts 5 years, although some centers now monitor patients beyond this point.
• To investigate the potential benefit of extended surveillance, researchers used Korean National Health Insurance claims data to identify 40,468 patients with gastric cancer who were disease free 5 years after gastrectomy — 14,294 received extended regular follow-up visits and 26,174 did not.
• The extended regular follow-up group was defined as having endoscopy or abdominopelvic CT between 2 months and 2 years before diagnosis of late recurrence or gastric remnant cancer and having two or more examinations between 5.5 and 8.5 years after gastrectomy. Late recurrence was a recurrence diagnosed 5 years after gastrectomy.
• Researchers used Cox proportional hazards regression to evaluate the independent association between follow-up and overall and postrecurrence survival rates.

TAKEAWAY:

• Overall, 5 years postgastrectomy, the incidence of late recurrence or gastric remnant cancer was 7.8% — 4.0% between 5 and 10 years (1610 of 40,468 patients) and 9.4% after 10 years (1528 of 16,287 patients).
• Regular follow-up beyond 5 years was associated with a significant reduction in overall mortality — from 49.4% to 36.9% at 15 years (P < .001). Overall survival after late recurrence or gastric remnant cancer also improved significantly with extended regular follow-up, with the 5-year postrecurrence survival rate increasing from 32.7% to 71.1% (P < .001).
• The combination of endoscopy and abdominopelvic CT provided the highest 5-year postrecurrence survival rate (74.5%), compared with endoscopy alone (54.5%) or CT alone (47.1%).
• A time interval of more than 2 years between a previous endoscopy or abdominopelvic CT and diagnosis of late recurrence or gastric remnant cancer significantly decreased postrecurrence survival (hazard ratio [HR], 1.72 for endoscopy and HR, 1.48 for abdominopelvic CT).

IN PRACTICE:

“These findings suggest that extended regular follow-up after 5 years post gastrectomy should be implemented clinically and that current practice and value of follow-up protocols in postoperative care of patients with gastric cancer be reconsidered,” the authors concluded.

The authors of an accompanying commentary cautioned that, while the study “successfully establishes groundwork for extending surveillance of gastric cancer in high-risk populations, more work is needed to strategically identify those who would benefit most from extended surveillance.”
 

SOURCE:

The study, with first author Ju-Hee Lee, MD, PhD, Department of Surgery, Hanyang University College of Medicine, Seoul, South Korea, and accompanying commentary were published online on June 18 in JAMA Surgery.

LIMITATIONS:

Recurrent cancer and gastric remnant cancer could not be distinguished from each other because clinical records were not analyzed. The claims database lacked detailed clinical information on individual patients, including cancer stages, and a separate analysis of tumor markers could not be performed.

DISCLOSURES:

The study was funded by a grant from the Korean Gastric Cancer Association. The study authors and commentary authors reported no conflicts of interest.

A version of this article appeared on Medscape.com.

TOPLINE:

For patients with gastric cancer, extending regular follow-up beyond the typical 5 years after gastrectomy was associated with improved overall and post-recurrence survival rates, new data from a retrospective analysis showed.

METHODOLOGY:

• Currently, postgastrectomy cancer surveillance typically lasts 5 years, although some centers now monitor patients beyond this point.
• To investigate the potential benefit of extended surveillance, researchers used Korean National Health Insurance claims data to identify 40,468 patients with gastric cancer who were disease free 5 years after gastrectomy — 14,294 received extended regular follow-up visits and 26,174 did not.
• The extended regular follow-up group was defined as having endoscopy or abdominopelvic CT between 2 months and 2 years before diagnosis of late recurrence or gastric remnant cancer and having two or more examinations between 5.5 and 8.5 years after gastrectomy. Late recurrence was a recurrence diagnosed 5 years after gastrectomy.
• Researchers used Cox proportional hazards regression to evaluate the independent association between follow-up and overall and postrecurrence survival rates.

TAKEAWAY:

• Overall, 5 years postgastrectomy, the incidence of late recurrence or gastric remnant cancer was 7.8% — 4.0% between 5 and 10 years (1610 of 40,468 patients) and 9.4% after 10 years (1528 of 16,287 patients).
• Regular follow-up beyond 5 years was associated with a significant reduction in overall mortality — from 49.4% to 36.9% at 15 years (P < .001). Overall survival after late recurrence or gastric remnant cancer also improved significantly with extended regular follow-up, with the 5-year postrecurrence survival rate increasing from 32.7% to 71.1% (P < .001).
• The combination of endoscopy and abdominopelvic CT provided the highest 5-year postrecurrence survival rate (74.5%), compared with endoscopy alone (54.5%) or CT alone (47.1%).
• A time interval of more than 2 years between a previous endoscopy or abdominopelvic CT and diagnosis of late recurrence or gastric remnant cancer significantly decreased postrecurrence survival (hazard ratio [HR], 1.72 for endoscopy and HR, 1.48 for abdominopelvic CT).

IN PRACTICE:

“These findings suggest that extended regular follow-up after 5 years post gastrectomy should be implemented clinically and that current practice and value of follow-up protocols in postoperative care of patients with gastric cancer be reconsidered,” the authors concluded.

The authors of an accompanying commentary cautioned that, while the study “successfully establishes groundwork for extending surveillance of gastric cancer in high-risk populations, more work is needed to strategically identify those who would benefit most from extended surveillance.”
 

SOURCE:

The study, with first author Ju-Hee Lee, MD, PhD, Department of Surgery, Hanyang University College of Medicine, Seoul, South Korea, and accompanying commentary were published online on June 18 in JAMA Surgery.

LIMITATIONS:

Recurrent cancer and gastric remnant cancer could not be distinguished from each other because clinical records were not analyzed. The claims database lacked detailed clinical information on individual patients, including cancer stages, and a separate analysis of tumor markers could not be performed.

DISCLOSURES:

The study was funded by a grant from the Korean Gastric Cancer Association. The study authors and commentary authors reported no conflicts of interest.

A version of this article appeared on Medscape.com.

A growing body of evidence has shown that people who regularly take aspirin have a lower risk for colorectal cancer (CRC) and are less likely to die if they do develop the disease.

A 2020 meta-analysis, for instance, found that 325 mg of daily aspirin — the typical dose in a single tablet — conferred a 35% reduced risk of developing CRC, and a highly cited The Lancet study from 2010 found that a low dose of daily aspirin reduced the incidence of colon cancer by 24% and colon cancer deaths by 35% over 20 years.

The evidence surrounding aspirin and CRC is so intriguing that more than 70,000 people are currently participating in more than two dozen clinical studies worldwide, putting aspirin through its paces as an intervention in CRC.

But what, exactly, is aspirin doing?

We know that aspirin inhibits cyclooxygenase (COX) enzymes — COX-1 and COX-2, specifically — and that the COX-2 pathway is implicated in the development and progression of CRC, explained Marco Scarpa, MD, PhD, staff surgeon at the University of Padova in Padova, Italy.

“However, the new thing we’ve found is that aspirin may have a direct role in enhancing immunosurveillance,” Dr. Scarpa said in an interview.

In April, Dr. Scarpa’s team published a paper in Cancer describing a mechanism that provides deeper insight into the aspirin-CRC connection.

Dr. Scarpa heads up the IMMUNOREACT study group, a collaboration of dozens of researchers across Italy running studies on immunosurveillance in rectal cancer. In the baseline study, IMMUNOREACT 1, the team created and analyzed a database of records from 238 patients who underwent surgery for CRC at the Azienda Ospedale Università di Padova, Padova, Italy, from 2015 to 2019.

Using the same database, the latest findings from IMMUNOREACT 7 focused on the fate of the 31 patients (13%) who used aspirin regularly.

The researchers found that regular aspirin use did not appear to affect colorectal tumor stage at diagnosis, but tumor grading was significantly lower overall, especially in patients with BRAF mutations. Regular aspirin users were also less likely to have nodal metastases and metastatic lymph nodes, and this effect was more pronounced in patients with proximal (right-sided) colon cancer vs distal (left-sided).

Most notably, IMMUNOREACT 7 revealed that aspirin has beneficial effects on the CRC immune microenvironment.

The team found that aspirin directly boosts the presence of antigens on gastrointestinal epithelial tumor cells, which can direct the body’s immune response to combat the cancer.

At a macro level, the aspirin users in the study were more likely to have high levels of tumor-infiltrating lymphocytes (TILs). Dr. Scarpa’s team had previously shown that high levels of CD8+ and CD3+ TILs were predictive of successful neoadjuvant therapy in rectal cancer.

Cytotoxic CD8+ T cells are central to the anticancer immune response, and in the latest study, a high ratio of CD8+/CD3+ T cells was more common in aspirin users, suggesting a stronger presence of cancer-killing CD8+ cells. Expression of CD8 beta+, an activation marker of CD8+ cells, was also enhanced in aspirin users.

The most significant discovery, according to Dr. Scarpa, was that aspirin users were more likely to show high expression of CD80 on the surface of their rectal epithelial cells.

CD80 is a molecule that allows T cells to identify the tumor cell as foreign and kill it. Although cancer cells can downregulate their CD80 to avoid detection by T cells, the study suggests that aspirin appears to help foil this strategy by boosting the production of CD80 on the surface of the tumor cells.

The researchers confirmed the clinical findings by showing that aspirin increased CD80 gene expression in lab-cultivated CRC cells.

“We didn’t expect the activation through CD80,” said Dr. Scarpa. “This means that aspirin can act on this very first interaction between the epithelial cell and the CD8+ lymphocyte.”

Overall, these new data suggest that aspirin helps activate the immune system, which helps explain its potential chemopreventive effect in CRC.

However, one puzzling result was that aspirin boosted expression of PD-L1 genes in the CRC cells, said Joanna Davies, DPhil, an immunologist who heads up the San Diego Biomedical Research Institute, San Diego, California, and was not involved in the study.

PD-L1 serves as an “off” switch for patrolling T cells, which protects the tumor cell from being recognized.

“If aspirin is inducing PD-L1 on cancer cells, that is a potential problem,” said Dr. Davies. “An ideal therapy might be the combination of aspirin to enhance the CD8 T cells in the tumor and immune checkpoint blockade to block PD-L1.”

David Kerr, CBE, MD, DSc, agreed that high-dose aspirin plus immunotherapy might be “a wee bit more effective.” However, the combination would be blocked by the economics of drug development: “Will anybody ever do a trial of 10,000 patients to prove that? Not on your nelly,” said Dr. Kerr, professor of cancer medicine at the University of Oxford, Oxford, England.

Despite the small patient numbers in the study, Dr. Kerr felt encouraged by the IMMUNOREACT analysis. “It’s a plausible piece of science and some quite promising work on the tumor immune microenvironment and the effects of aspirin on it,” Dr. Kerr said in a recent commentary for this news organization.

Dr. Scarpa and Dr. Davies had no conflicts of interest to declare.

A version of this article appeared on Medscape.com .

A growing body of evidence has shown that people who regularly take aspirin have a lower risk for colorectal cancer (CRC) and are less likely to die if they do develop the disease.

A 2020 meta-analysis, for instance, found that 325 mg of daily aspirin — the typical dose in a single tablet — conferred a 35% reduced risk of developing CRC, and a highly cited The Lancet study from 2010 found that a low dose of daily aspirin reduced the incidence of colon cancer by 24% and colon cancer deaths by 35% over 20 years.

The evidence surrounding aspirin and CRC is so intriguing that more than 70,000 people are currently participating in more than two dozen clinical studies worldwide, putting aspirin through its paces as an intervention in CRC.

But what, exactly, is aspirin doing?

We know that aspirin inhibits cyclooxygenase (COX) enzymes — COX-1 and COX-2, specifically — and that the COX-2 pathway is implicated in the development and progression of CRC, explained Marco Scarpa, MD, PhD, staff surgeon at the University of Padova in Padova, Italy.

“However, the new thing we’ve found is that aspirin may have a direct role in enhancing immunosurveillance,” Dr. Scarpa said in an interview.

In April, Dr. Scarpa’s team published a paper in Cancer describing a mechanism that provides deeper insight into the aspirin-CRC connection.

Dr. Scarpa heads up the IMMUNOREACT study group, a collaboration of dozens of researchers across Italy running studies on immunosurveillance in rectal cancer. In the baseline study, IMMUNOREACT 1, the team created and analyzed a database of records from 238 patients who underwent surgery for CRC at the Azienda Ospedale Università di Padova, Padova, Italy, from 2015 to 2019.

Using the same database, the latest findings from IMMUNOREACT 7 focused on the fate of the 31 patients (13%) who used aspirin regularly.

The researchers found that regular aspirin use did not appear to affect colorectal tumor stage at diagnosis, but tumor grading was significantly lower overall, especially in patients with BRAF mutations. Regular aspirin users were also less likely to have nodal metastases and metastatic lymph nodes, and this effect was more pronounced in patients with proximal (right-sided) colon cancer vs distal (left-sided).

Most notably, IMMUNOREACT 7 revealed that aspirin has beneficial effects on the CRC immune microenvironment.

The team found that aspirin directly boosts the presence of antigens on gastrointestinal epithelial tumor cells, which can direct the body’s immune response to combat the cancer.

At a macro level, the aspirin users in the study were more likely to have high levels of tumor-infiltrating lymphocytes (TILs). Dr. Scarpa’s team had previously shown that high levels of CD8+ and CD3+ TILs were predictive of successful neoadjuvant therapy in rectal cancer.

Cytotoxic CD8+ T cells are central to the anticancer immune response, and in the latest study, a high ratio of CD8+/CD3+ T cells was more common in aspirin users, suggesting a stronger presence of cancer-killing CD8+ cells. Expression of CD8 beta+, an activation marker of CD8+ cells, was also enhanced in aspirin users.

The most significant discovery, according to Dr. Scarpa, was that aspirin users were more likely to show high expression of CD80 on the surface of their rectal epithelial cells.

CD80 is a molecule that allows T cells to identify the tumor cell as foreign and kill it. Although cancer cells can downregulate their CD80 to avoid detection by T cells, the study suggests that aspirin appears to help foil this strategy by boosting the production of CD80 on the surface of the tumor cells.

The researchers confirmed the clinical findings by showing that aspirin increased CD80 gene expression in lab-cultivated CRC cells.

“We didn’t expect the activation through CD80,” said Dr. Scarpa. “This means that aspirin can act on this very first interaction between the epithelial cell and the CD8+ lymphocyte.”

Overall, these new data suggest that aspirin helps activate the immune system, which helps explain its potential chemopreventive effect in CRC.

However, one puzzling result was that aspirin boosted expression of PD-L1 genes in the CRC cells, said Joanna Davies, DPhil, an immunologist who heads up the San Diego Biomedical Research Institute, San Diego, California, and was not involved in the study.

PD-L1 serves as an “off” switch for patrolling T cells, which protects the tumor cell from being recognized.

“If aspirin is inducing PD-L1 on cancer cells, that is a potential problem,” said Dr. Davies. “An ideal therapy might be the combination of aspirin to enhance the CD8 T cells in the tumor and immune checkpoint blockade to block PD-L1.”

David Kerr, CBE, MD, DSc, agreed that high-dose aspirin plus immunotherapy might be “a wee bit more effective.” However, the combination would be blocked by the economics of drug development: “Will anybody ever do a trial of 10,000 patients to prove that? Not on your nelly,” said Dr. Kerr, professor of cancer medicine at the University of Oxford, Oxford, England.

Despite the small patient numbers in the study, Dr. Kerr felt encouraged by the IMMUNOREACT analysis. “It’s a plausible piece of science and some quite promising work on the tumor immune microenvironment and the effects of aspirin on it,” Dr. Kerr said in a recent commentary for this news organization.

Dr. Scarpa and Dr. Davies had no conflicts of interest to declare.

A version of this article appeared on Medscape.com .

A growing body of evidence has shown that people who regularly take aspirin have a lower risk for colorectal cancer (CRC) and are less likely to die if they do develop the disease.

A 2020 meta-analysis, for instance, found that 325 mg of daily aspirin — the typical dose in a single tablet — conferred a 35% reduced risk of developing CRC, and a highly cited The Lancet study from 2010 found that a low dose of daily aspirin reduced the incidence of colon cancer by 24% and colon cancer deaths by 35% over 20 years.

The evidence surrounding aspirin and CRC is so intriguing that more than 70,000 people are currently participating in more than two dozen clinical studies worldwide, putting aspirin through its paces as an intervention in CRC.

But what, exactly, is aspirin doing?

We know that aspirin inhibits cyclooxygenase (COX) enzymes — COX-1 and COX-2, specifically — and that the COX-2 pathway is implicated in the development and progression of CRC, explained Marco Scarpa, MD, PhD, staff surgeon at the University of Padova in Padova, Italy.

“However, the new thing we’ve found is that aspirin may have a direct role in enhancing immunosurveillance,” Dr. Scarpa said in an interview.

In April, Dr. Scarpa’s team published a paper in Cancer describing a mechanism that provides deeper insight into the aspirin-CRC connection.

Dr. Scarpa heads up the IMMUNOREACT study group, a collaboration of dozens of researchers across Italy running studies on immunosurveillance in rectal cancer. In the baseline study, IMMUNOREACT 1, the team created and analyzed a database of records from 238 patients who underwent surgery for CRC at the Azienda Ospedale Università di Padova, Padova, Italy, from 2015 to 2019.

Using the same database, the latest findings from IMMUNOREACT 7 focused on the fate of the 31 patients (13%) who used aspirin regularly.

The researchers found that regular aspirin use did not appear to affect colorectal tumor stage at diagnosis, but tumor grading was significantly lower overall, especially in patients with BRAF mutations. Regular aspirin users were also less likely to have nodal metastases and metastatic lymph nodes, and this effect was more pronounced in patients with proximal (right-sided) colon cancer vs distal (left-sided).

Most notably, IMMUNOREACT 7 revealed that aspirin has beneficial effects on the CRC immune microenvironment.

The team found that aspirin directly boosts the presence of antigens on gastrointestinal epithelial tumor cells, which can direct the body’s immune response to combat the cancer.

At a macro level, the aspirin users in the study were more likely to have high levels of tumor-infiltrating lymphocytes (TILs). Dr. Scarpa’s team had previously shown that high levels of CD8+ and CD3+ TILs were predictive of successful neoadjuvant therapy in rectal cancer.

Cytotoxic CD8+ T cells are central to the anticancer immune response, and in the latest study, a high ratio of CD8+/CD3+ T cells was more common in aspirin users, suggesting a stronger presence of cancer-killing CD8+ cells. Expression of CD8 beta+, an activation marker of CD8+ cells, was also enhanced in aspirin users.

The most significant discovery, according to Dr. Scarpa, was that aspirin users were more likely to show high expression of CD80 on the surface of their rectal epithelial cells.

CD80 is a molecule that allows T cells to identify the tumor cell as foreign and kill it. Although cancer cells can downregulate their CD80 to avoid detection by T cells, the study suggests that aspirin appears to help foil this strategy by boosting the production of CD80 on the surface of the tumor cells.

The researchers confirmed the clinical findings by showing that aspirin increased CD80 gene expression in lab-cultivated CRC cells.

“We didn’t expect the activation through CD80,” said Dr. Scarpa. “This means that aspirin can act on this very first interaction between the epithelial cell and the CD8+ lymphocyte.”

Overall, these new data suggest that aspirin helps activate the immune system, which helps explain its potential chemopreventive effect in CRC.

However, one puzzling result was that aspirin boosted expression of PD-L1 genes in the CRC cells, said Joanna Davies, DPhil, an immunologist who heads up the San Diego Biomedical Research Institute, San Diego, California, and was not involved in the study.

PD-L1 serves as an “off” switch for patrolling T cells, which protects the tumor cell from being recognized.

“If aspirin is inducing PD-L1 on cancer cells, that is a potential problem,” said Dr. Davies. “An ideal therapy might be the combination of aspirin to enhance the CD8 T cells in the tumor and immune checkpoint blockade to block PD-L1.”

David Kerr, CBE, MD, DSc, agreed that high-dose aspirin plus immunotherapy might be “a wee bit more effective.” However, the combination would be blocked by the economics of drug development: “Will anybody ever do a trial of 10,000 patients to prove that? Not on your nelly,” said Dr. Kerr, professor of cancer medicine at the University of Oxford, Oxford, England.

Despite the small patient numbers in the study, Dr. Kerr felt encouraged by the IMMUNOREACT analysis. “It’s a plausible piece of science and some quite promising work on the tumor immune microenvironment and the effects of aspirin on it,” Dr. Kerr said in a recent commentary for this news organization.

Dr. Scarpa and Dr. Davies had no conflicts of interest to declare.

A version of this article appeared on Medscape.com .

When doctors and patients consider the appendix, it’s often with urgency. In cases of appendicitis, the clock could be ticking down to a life-threatening burst. Thus, despite recent research suggesting antibiotics could be an alternative therapy, appendectomy remains standard for uncomplicated appendicitis.

But what if removing the appendix could raise the risk for gastrointestinal (GI) diseases like irritable bowel syndrome and colorectal cancer? That’s what some emerging science suggests. And though the research is early and mixed, it’s enough to give some health professionals pause.

“If there’s no reason to remove the appendix, then it’s better to have one,” said Heather Smith, PhD, a comparative anatomist at Midwestern University, Glendale, Arizona. Preemptive removal is not supported by the evidence, she said.

To be fair, we’ve come a long way since 1928, when American physician Miles Breuer, MD, suggested that people with infected appendixes should be left to perish, so as to remove their inferior DNA from the gene pool (he called such people “uncivilized” and “candidates for extinction”). Charles Darwin, while less radical, believed the appendix was at best useless — a mere vestige of our ancestors switching diets from leaves to fruits.

What we know now is that the appendix isn’t just a troublesome piece of worthless flesh. Instead, it may act as a safe house for friendly gut bacteria and a training camp for the immune system. It also appears to play a role in several medical conditions, from ulcerative colitis and colorectal cancer to Parkinson’s disease and lupus. The roughly 300,000 Americans who undergo appendectomy each year should be made aware of this, some experts say. But the frustrating truth is, scientists are still trying to figure out in which cases having an appendix is protective and in which we may be better off without it.
 

A ‘Worm’ as Intestinal Protection

The appendix is a blind pouch (meaning its ending is closed off) that extends from the large intestine. Not all mammals have one; it’s been found in several species of primates and rodents, as well as in rabbits, wombats, and Florida manatees, among others (dogs and cats don’t have it). While a human appendix “looks like a little worm,” Dr. Smith said, these anatomical structures come in various sizes and shapes. Some are thick, as in a beaver, while others are long and spiraling, like a rabbit’s.

Comparative anatomy studies reveal that the appendix has evolved independently at least 29 times throughout mammalian evolution. This suggests that “it has some kind of an adaptive function,” Dr. Smith said. When French scientists analyzed data from 258 species of mammals, they discovered that those that possess an appendix live longer than those without one. A possible explanation, the researchers wrote, may lie with the appendix’s role in preventing diarrhea.

Their 2023 study supported this hypothesis. Based on veterinary records of 45 different species of primates housed in a French zoo, the scientists established that primates with appendixes are far less likely to suffer severe diarrhea than those that don’t possess this organ. The appendix, it appears, might be our tiny weapon against bowel troubles.

For immunologist William Parker, PhD, a visiting scholar at the University of North Carolina at Chapel Hill, these data are “about as good as we could hope for” in support of the idea that the appendix might protect mammals from GI problems. An experiment on humans would be unethical, Dr. Parker said. But observational studies offer clues.

One study showed that compared with people with an intact appendix, young adults with a history of appendectomy have more than double the risk of developing a serious infection with non-typhoidal Salmonella of the kind that would require hospitalization.
 

A ‘Safe House’ for Bacteria

Such studies add weight to a theory that Dr. Parker and his colleagues developed back in 2007: That the appendix acts as a “safe house” for beneficial gut bacteria.

Think of the colon as a wide pipe, Dr. Parker said, that may become contaminated with a pathogen such as Salmonella. Diarrhea follows, and the pipe gets repeatedly flushed, wiping everything clean, including your friendly gut microbiome. Luckily, “you’ve got this little offshoot of that pipe,” where the flow can’t really get in “because it’s so constricted,” Dr. Parker said. The friendly gut microbes can survive inside the appendix and repopulate the colon once diarrhea is over. Dr. Parker and his colleagues found that the human appendix contains a thick layer of beneficial bacteria. “They were right where we predicted they would be,” he said.

This safe house hypothesis could explain why the gut microbiome may be different in people who no longer have an appendix. In one small study, people who’d had an appendectomy had a less diverse microbiome, with a lower abundance of beneficial strains such as Butyricicoccus and Barnesiella, than did those with intact appendixes.

The appendix likely has a second function, too, Dr. Smith said: It may serve as a training camp for the immune system. “When there is an invading pathogen in the gut, it helps the GI system to mount the immune response,” she said. The human appendix is rich in special cells known as M cells. These act as scouts, detecting and capturing invasive bacteria and viruses and presenting them to the body’s defense team, such as the T lymphocytes.

If the appendix shelters beneficial bacteria and boosts immune response, that may explain its links to various diseases. According to an epidemiological study from Taiwan,patients who underwent an appendectomy have a 46% higher risk of developing irritable bowel syndrome (IBS) — a disease associated with a low abundance of Butyricicoccus bacteria. This is why, the study authors wrote, doctors should pay careful attention to people who’ve had their appendixes removed, monitoring them for potential symptoms of IBS.

The same database helped uncover other connections between appendectomy and disease. For one, there was type 2 diabetes: Within 3 years of the surgery, patients under 30 had double the risk of developing this disorder. Then there was lupus: While those who underwent appendectomy generally had higher risk for this autoimmune disease, women were particularly affected.
 

The Contentious Connections

The most heated scientific discussion surrounds the links between the appendix and conditions such as Parkinson’s disease, ulcerative colitis, and colorectal cancer. A small 2019 study showed, for example, that appendectomy may improve symptoms of certain forms of ulcerative colitis that don’t respond to standard medical treatments. A third of patients improved after their appendix was removed, and 17% fully recovered.

Why? According to Dr. Parker, appendectomy may work for ulcerative colitis because it’s “a way of suppressing the immune system, especially in the lower intestinal areas.” A 2023 meta-analysis found that people who’d had their appendix removed before being diagnosed with ulcerative colitis were less likely to need their colon removed later on.

Such a procedure may have a serious side effect, however: Colorectal cancer. French scientists discovered that removing the appendix may reduce the numbers of certain immune cells called CD3+ and CD8+ T cells, causing a weakened immune surveillance. As a result, tumor cells might escape detection.

Yet the links between appendix removal and cancer are far from clear. A recent meta-analysis found that while people with appendectomies generally had a higher risk for colorectal cancer, for Europeans, these effects were insignificant. In fact, removal of the appendix actually protected European women from this particular form of cancer. For Parker, such mixed results may stem from the fact that treatments and populations vary widely. The issue “may depend on complex social and medical factors,” Dr. Parker said.

Things also appear complicated with Parkinson’s disease — another condition linked to the appendix. A large epidemiological study showed that appendectomy is associated with a lower risk for Parkinson’s disease and a delayed age of Parkinson’s onset. It also found that a normal appendix contains α-synuclein, a protein that may accumulate in the brain and contribute to the development of Parkinson’s. “Although α-synuclein is toxic when in the brain, it appears to be quite normal when present in the appendix,” said Luis Vitetta, PhD, MD, a clinical epidemiologist at the University of Sydney, Camperdown, Australia. Yet, not all studies find that removing the appendix lowers the risk for Parkinson’s. In fact, some show the opposite results.
 

How Should Doctors View the Appendix?

Even with these mysteries and contradictions, Dr. Vitetta said, a healthy appendix in a healthy body appears to be protective. This is why, he said, when someone is diagnosed with appendicitis, careful assessment is essential before surgery is performed.

“Perhaps an antibiotic can actually help fix it,” he said. A 2020 study published in The New England Journal of Medicine showed that antibiotics may indeed be a good alternative to surgery for the treatment of appendicitis. “We don’t want necessarily to remove an appendix that could be beneficial,” Dr. Smith said.

The many links between the appendix and various diseases mean that doctors should be more vigilant when treating patients who’ve had this organ removed, Dr. Parker said. “When a patient loses an appendix, depending on their environment, there may be effects on infection and cancer. So they might need more regular checkups,” he said. This could include monitoring for IBS and colorectal cancer.

What’s more, Dr. Parker believes that research on the appendix puts even more emphasis on the need to protect the gut microbiome — such as taking probiotics with antibiotics. And while we are still a long way from understanding how exactly this worm-like structure affects various diseases, one thing appears quite certain: The appendix is not useless. “If Darwin had the information that we have, he would not have drawn these conclusions,” Dr. Parker said.
 

A version of this article first appeared on Medscape.com.

When doctors and patients consider the appendix, it’s often with urgency. In cases of appendicitis, the clock could be ticking down to a life-threatening burst. Thus, despite recent research suggesting antibiotics could be an alternative therapy, appendectomy remains standard for uncomplicated appendicitis.

But what if removing the appendix could raise the risk for gastrointestinal (GI) diseases like irritable bowel syndrome and colorectal cancer? That’s what some emerging science suggests. And though the research is early and mixed, it’s enough to give some health professionals pause.

“If there’s no reason to remove the appendix, then it’s better to have one,” said Heather Smith, PhD, a comparative anatomist at Midwestern University, Glendale, Arizona. Preemptive removal is not supported by the evidence, she said.

To be fair, we’ve come a long way since 1928, when American physician Miles Breuer, MD, suggested that people with infected appendixes should be left to perish, so as to remove their inferior DNA from the gene pool (he called such people “uncivilized” and “candidates for extinction”). Charles Darwin, while less radical, believed the appendix was at best useless — a mere vestige of our ancestors switching diets from leaves to fruits.

What we know now is that the appendix isn’t just a troublesome piece of worthless flesh. Instead, it may act as a safe house for friendly gut bacteria and a training camp for the immune system. It also appears to play a role in several medical conditions, from ulcerative colitis and colorectal cancer to Parkinson’s disease and lupus. The roughly 300,000 Americans who undergo appendectomy each year should be made aware of this, some experts say. But the frustrating truth is, scientists are still trying to figure out in which cases having an appendix is protective and in which we may be better off without it.
 

A ‘Worm’ as Intestinal Protection

The appendix is a blind pouch (meaning its ending is closed off) that extends from the large intestine. Not all mammals have one; it’s been found in several species of primates and rodents, as well as in rabbits, wombats, and Florida manatees, among others (dogs and cats don’t have it). While a human appendix “looks like a little worm,” Dr. Smith said, these anatomical structures come in various sizes and shapes. Some are thick, as in a beaver, while others are long and spiraling, like a rabbit’s.

Comparative anatomy studies reveal that the appendix has evolved independently at least 29 times throughout mammalian evolution. This suggests that “it has some kind of an adaptive function,” Dr. Smith said. When French scientists analyzed data from 258 species of mammals, they discovered that those that possess an appendix live longer than those without one. A possible explanation, the researchers wrote, may lie with the appendix’s role in preventing diarrhea.

Their 2023 study supported this hypothesis. Based on veterinary records of 45 different species of primates housed in a French zoo, the scientists established that primates with appendixes are far less likely to suffer severe diarrhea than those that don’t possess this organ. The appendix, it appears, might be our tiny weapon against bowel troubles.

For immunologist William Parker, PhD, a visiting scholar at the University of North Carolina at Chapel Hill, these data are “about as good as we could hope for” in support of the idea that the appendix might protect mammals from GI problems. An experiment on humans would be unethical, Dr. Parker said. But observational studies offer clues.

One study showed that compared with people with an intact appendix, young adults with a history of appendectomy have more than double the risk of developing a serious infection with non-typhoidal Salmonella of the kind that would require hospitalization.
 

A ‘Safe House’ for Bacteria

Such studies add weight to a theory that Dr. Parker and his colleagues developed back in 2007: That the appendix acts as a “safe house” for beneficial gut bacteria.

Think of the colon as a wide pipe, Dr. Parker said, that may become contaminated with a pathogen such as Salmonella. Diarrhea follows, and the pipe gets repeatedly flushed, wiping everything clean, including your friendly gut microbiome. Luckily, “you’ve got this little offshoot of that pipe,” where the flow can’t really get in “because it’s so constricted,” Dr. Parker said. The friendly gut microbes can survive inside the appendix and repopulate the colon once diarrhea is over. Dr. Parker and his colleagues found that the human appendix contains a thick layer of beneficial bacteria. “They were right where we predicted they would be,” he said.

This safe house hypothesis could explain why the gut microbiome may be different in people who no longer have an appendix. In one small study, people who’d had an appendectomy had a less diverse microbiome, with a lower abundance of beneficial strains such as Butyricicoccus and Barnesiella, than did those with intact appendixes.

The appendix likely has a second function, too, Dr. Smith said: It may serve as a training camp for the immune system. “When there is an invading pathogen in the gut, it helps the GI system to mount the immune response,” she said. The human appendix is rich in special cells known as M cells. These act as scouts, detecting and capturing invasive bacteria and viruses and presenting them to the body’s defense team, such as the T lymphocytes.

If the appendix shelters beneficial bacteria and boosts immune response, that may explain its links to various diseases. According to an epidemiological study from Taiwan,patients who underwent an appendectomy have a 46% higher risk of developing irritable bowel syndrome (IBS) — a disease associated with a low abundance of Butyricicoccus bacteria. This is why, the study authors wrote, doctors should pay careful attention to people who’ve had their appendixes removed, monitoring them for potential symptoms of IBS.

The same database helped uncover other connections between appendectomy and disease. For one, there was type 2 diabetes: Within 3 years of the surgery, patients under 30 had double the risk of developing this disorder. Then there was lupus: While those who underwent appendectomy generally had higher risk for this autoimmune disease, women were particularly affected.
 

The Contentious Connections

The most heated scientific discussion surrounds the links between the appendix and conditions such as Parkinson’s disease, ulcerative colitis, and colorectal cancer. A small 2019 study showed, for example, that appendectomy may improve symptoms of certain forms of ulcerative colitis that don’t respond to standard medical treatments. A third of patients improved after their appendix was removed, and 17% fully recovered.

Why? According to Dr. Parker, appendectomy may work for ulcerative colitis because it’s “a way of suppressing the immune system, especially in the lower intestinal areas.” A 2023 meta-analysis found that people who’d had their appendix removed before being diagnosed with ulcerative colitis were less likely to need their colon removed later on.

Such a procedure may have a serious side effect, however: Colorectal cancer. French scientists discovered that removing the appendix may reduce the numbers of certain immune cells called CD3+ and CD8+ T cells, causing a weakened immune surveillance. As a result, tumor cells might escape detection.

Yet the links between appendix removal and cancer are far from clear. A recent meta-analysis found that while people with appendectomies generally had a higher risk for colorectal cancer, for Europeans, these effects were insignificant. In fact, removal of the appendix actually protected European women from this particular form of cancer. For Parker, such mixed results may stem from the fact that treatments and populations vary widely. The issue “may depend on complex social and medical factors,” Dr. Parker said.

Things also appear complicated with Parkinson’s disease — another condition linked to the appendix. A large epidemiological study showed that appendectomy is associated with a lower risk for Parkinson’s disease and a delayed age of Parkinson’s onset. It also found that a normal appendix contains α-synuclein, a protein that may accumulate in the brain and contribute to the development of Parkinson’s. “Although α-synuclein is toxic when in the brain, it appears to be quite normal when present in the appendix,” said Luis Vitetta, PhD, MD, a clinical epidemiologist at the University of Sydney, Camperdown, Australia. Yet, not all studies find that removing the appendix lowers the risk for Parkinson’s. In fact, some show the opposite results.
 

How Should Doctors View the Appendix?

Even with these mysteries and contradictions, Dr. Vitetta said, a healthy appendix in a healthy body appears to be protective. This is why, he said, when someone is diagnosed with appendicitis, careful assessment is essential before surgery is performed.

“Perhaps an antibiotic can actually help fix it,” he said. A 2020 study published in The New England Journal of Medicine showed that antibiotics may indeed be a good alternative to surgery for the treatment of appendicitis. “We don’t want necessarily to remove an appendix that could be beneficial,” Dr. Smith said.

The many links between the appendix and various diseases mean that doctors should be more vigilant when treating patients who’ve had this organ removed, Dr. Parker said. “When a patient loses an appendix, depending on their environment, there may be effects on infection and cancer. So they might need more regular checkups,” he said. This could include monitoring for IBS and colorectal cancer.

What’s more, Dr. Parker believes that research on the appendix puts even more emphasis on the need to protect the gut microbiome — such as taking probiotics with antibiotics. And while we are still a long way from understanding how exactly this worm-like structure affects various diseases, one thing appears quite certain: The appendix is not useless. “If Darwin had the information that we have, he would not have drawn these conclusions,” Dr. Parker said.
 

A version of this article first appeared on Medscape.com.

When doctors and patients consider the appendix, it’s often with urgency. In cases of appendicitis, the clock could be ticking down to a life-threatening burst. Thus, despite recent research suggesting antibiotics could be an alternative therapy, appendectomy remains standard for uncomplicated appendicitis.

But what if removing the appendix could raise the risk for gastrointestinal (GI) diseases like irritable bowel syndrome and colorectal cancer? That’s what some emerging science suggests. And though the research is early and mixed, it’s enough to give some health professionals pause.

“If there’s no reason to remove the appendix, then it’s better to have one,” said Heather Smith, PhD, a comparative anatomist at Midwestern University, Glendale, Arizona. Preemptive removal is not supported by the evidence, she said.

To be fair, we’ve come a long way since 1928, when American physician Miles Breuer, MD, suggested that people with infected appendixes should be left to perish, so as to remove their inferior DNA from the gene pool (he called such people “uncivilized” and “candidates for extinction”). Charles Darwin, while less radical, believed the appendix was at best useless — a mere vestige of our ancestors switching diets from leaves to fruits.

What we know now is that the appendix isn’t just a troublesome piece of worthless flesh. Instead, it may act as a safe house for friendly gut bacteria and a training camp for the immune system. It also appears to play a role in several medical conditions, from ulcerative colitis and colorectal cancer to Parkinson’s disease and lupus. The roughly 300,000 Americans who undergo appendectomy each year should be made aware of this, some experts say. But the frustrating truth is, scientists are still trying to figure out in which cases having an appendix is protective and in which we may be better off without it.
 

A ‘Worm’ as Intestinal Protection

The appendix is a blind pouch (meaning its ending is closed off) that extends from the large intestine. Not all mammals have one; it’s been found in several species of primates and rodents, as well as in rabbits, wombats, and Florida manatees, among others (dogs and cats don’t have it). While a human appendix “looks like a little worm,” Dr. Smith said, these anatomical structures come in various sizes and shapes. Some are thick, as in a beaver, while others are long and spiraling, like a rabbit’s.

Comparative anatomy studies reveal that the appendix has evolved independently at least 29 times throughout mammalian evolution. This suggests that “it has some kind of an adaptive function,” Dr. Smith said. When French scientists analyzed data from 258 species of mammals, they discovered that those that possess an appendix live longer than those without one. A possible explanation, the researchers wrote, may lie with the appendix’s role in preventing diarrhea.

Their 2023 study supported this hypothesis. Based on veterinary records of 45 different species of primates housed in a French zoo, the scientists established that primates with appendixes are far less likely to suffer severe diarrhea than those that don’t possess this organ. The appendix, it appears, might be our tiny weapon against bowel troubles.

For immunologist William Parker, PhD, a visiting scholar at the University of North Carolina at Chapel Hill, these data are “about as good as we could hope for” in support of the idea that the appendix might protect mammals from GI problems. An experiment on humans would be unethical, Dr. Parker said. But observational studies offer clues.

One study showed that compared with people with an intact appendix, young adults with a history of appendectomy have more than double the risk of developing a serious infection with non-typhoidal Salmonella of the kind that would require hospitalization.
 

A ‘Safe House’ for Bacteria

Such studies add weight to a theory that Dr. Parker and his colleagues developed back in 2007: That the appendix acts as a “safe house” for beneficial gut bacteria.

Think of the colon as a wide pipe, Dr. Parker said, that may become contaminated with a pathogen such as Salmonella. Diarrhea follows, and the pipe gets repeatedly flushed, wiping everything clean, including your friendly gut microbiome. Luckily, “you’ve got this little offshoot of that pipe,” where the flow can’t really get in “because it’s so constricted,” Dr. Parker said. The friendly gut microbes can survive inside the appendix and repopulate the colon once diarrhea is over. Dr. Parker and his colleagues found that the human appendix contains a thick layer of beneficial bacteria. “They were right where we predicted they would be,” he said.

This safe house hypothesis could explain why the gut microbiome may be different in people who no longer have an appendix. In one small study, people who’d had an appendectomy had a less diverse microbiome, with a lower abundance of beneficial strains such as Butyricicoccus and Barnesiella, than did those with intact appendixes.

The appendix likely has a second function, too, Dr. Smith said: It may serve as a training camp for the immune system. “When there is an invading pathogen in the gut, it helps the GI system to mount the immune response,” she said. The human appendix is rich in special cells known as M cells. These act as scouts, detecting and capturing invasive bacteria and viruses and presenting them to the body’s defense team, such as the T lymphocytes.

If the appendix shelters beneficial bacteria and boosts immune response, that may explain its links to various diseases. According to an epidemiological study from Taiwan,patients who underwent an appendectomy have a 46% higher risk of developing irritable bowel syndrome (IBS) — a disease associated with a low abundance of Butyricicoccus bacteria. This is why, the study authors wrote, doctors should pay careful attention to people who’ve had their appendixes removed, monitoring them for potential symptoms of IBS.

The same database helped uncover other connections between appendectomy and disease. For one, there was type 2 diabetes: Within 3 years of the surgery, patients under 30 had double the risk of developing this disorder. Then there was lupus: While those who underwent appendectomy generally had higher risk for this autoimmune disease, women were particularly affected.
 

The Contentious Connections

The most heated scientific discussion surrounds the links between the appendix and conditions such as Parkinson’s disease, ulcerative colitis, and colorectal cancer. A small 2019 study showed, for example, that appendectomy may improve symptoms of certain forms of ulcerative colitis that don’t respond to standard medical treatments. A third of patients improved after their appendix was removed, and 17% fully recovered.

Why? According to Dr. Parker, appendectomy may work for ulcerative colitis because it’s “a way of suppressing the immune system, especially in the lower intestinal areas.” A 2023 meta-analysis found that people who’d had their appendix removed before being diagnosed with ulcerative colitis were less likely to need their colon removed later on.

Such a procedure may have a serious side effect, however: Colorectal cancer. French scientists discovered that removing the appendix may reduce the numbers of certain immune cells called CD3+ and CD8+ T cells, causing a weakened immune surveillance. As a result, tumor cells might escape detection.

Yet the links between appendix removal and cancer are far from clear. A recent meta-analysis found that while people with appendectomies generally had a higher risk for colorectal cancer, for Europeans, these effects were insignificant. In fact, removal of the appendix actually protected European women from this particular form of cancer. For Parker, such mixed results may stem from the fact that treatments and populations vary widely. The issue “may depend on complex social and medical factors,” Dr. Parker said.

Things also appear complicated with Parkinson’s disease — another condition linked to the appendix. A large epidemiological study showed that appendectomy is associated with a lower risk for Parkinson’s disease and a delayed age of Parkinson’s onset. It also found that a normal appendix contains α-synuclein, a protein that may accumulate in the brain and contribute to the development of Parkinson’s. “Although α-synuclein is toxic when in the brain, it appears to be quite normal when present in the appendix,” said Luis Vitetta, PhD, MD, a clinical epidemiologist at the University of Sydney, Camperdown, Australia. Yet, not all studies find that removing the appendix lowers the risk for Parkinson’s. In fact, some show the opposite results.
 

How Should Doctors View the Appendix?

Even with these mysteries and contradictions, Dr. Vitetta said, a healthy appendix in a healthy body appears to be protective. This is why, he said, when someone is diagnosed with appendicitis, careful assessment is essential before surgery is performed.

“Perhaps an antibiotic can actually help fix it,” he said. A 2020 study published in The New England Journal of Medicine showed that antibiotics may indeed be a good alternative to surgery for the treatment of appendicitis. “We don’t want necessarily to remove an appendix that could be beneficial,” Dr. Smith said.

The many links between the appendix and various diseases mean that doctors should be more vigilant when treating patients who’ve had this organ removed, Dr. Parker said. “When a patient loses an appendix, depending on their environment, there may be effects on infection and cancer. So they might need more regular checkups,” he said. This could include monitoring for IBS and colorectal cancer.

What’s more, Dr. Parker believes that research on the appendix puts even more emphasis on the need to protect the gut microbiome — such as taking probiotics with antibiotics. And while we are still a long way from understanding how exactly this worm-like structure affects various diseases, one thing appears quite certain: The appendix is not useless. “If Darwin had the information that we have, he would not have drawn these conclusions,” Dr. Parker said.
 

A version of this article first appeared on Medscape.com.

CHICAGO — Genetics and diet have been among the top theories for what may be fueling the troubling rise of colorectal cancer in young adults. Now, an early look at genetic data from people with colorectal cancer further suggests that the cause is linked to what is happening in the gut.

The findings were presented at the annual meeting of the American Society for Clinical Oncology (ASCO) by researchers from Ohio State University. For the analysis, they analyzed genetic data on tumors.

The researchers found signs that a high-fat, low-fiber diet may increase inflammation in the gut that prevents it from naturally suppressing tumors. The cells of young people with colorectal cancer also appeared to have aged more quickly — by 15 years on average — than a person’s actual age. That’s unusual, because older people with colorectal cancer don’t have the same boost in cellular aging.

The rate of colorectal cancer among young people has been rising at an alarming rate, according to a 2023 report from the American Cancer Society. In 2019, one in five colorectal cancer cases were among people younger than 55. That’s up from 1 in 10 in 1995, which means the rate has doubled in less than 30 years.
 

Need Colon Cancer Screening?

Who needs a colorectal cancer screening? Ask colorectal cancer specialist Nancy Kemeny, MD.

A 2017 analysis estimated that a person’s risk of colorectal cancer increased 12% by eating 3.5 ounces of red or processed meat daily, which is the equivalent of the size of a deck of playing cards. The same study also linked colorectal cancer risk to alcohol intake, citing its ethanol content. Eating a diet high in fiber can reduce a person’s risk.

This latest study aligned with previous findings that link bacteria called Fusobacterium to colorectal cancer. It’s not unusual for Fusobacterium to be present in a person’s mouth, but it is more likely to be found in the intestines of colorectal cancer patients, compared with those of healthy people. One study even found that people with colorectal cancer were five times more likely to have Fusobacterium in their stool, compared with healthy people.

Colorectal cancer is more common among men than women, “likely reflecting differences in risk factor prevalence, such as excess body weight and processed meat consumption,” the authors of the 2023 American Cancer Society report explained.

People younger than 45 should alert their medical provider if they have constipation, rectal bleeding, or sudden changes in bowel movements, which can be symptoms of colorectal cancer. Screening for colorectal cancer should begin for most people at age 45.

A version of this article appeared on WebMD.com.

CHICAGO — Genetics and diet have been among the top theories for what may be fueling the troubling rise of colorectal cancer in young adults. Now, an early look at genetic data from people with colorectal cancer further suggests that the cause is linked to what is happening in the gut.

The findings were presented at the annual meeting of the American Society for Clinical Oncology (ASCO) by researchers from Ohio State University. For the analysis, they analyzed genetic data on tumors.

The researchers found signs that a high-fat, low-fiber diet may increase inflammation in the gut that prevents it from naturally suppressing tumors. The cells of young people with colorectal cancer also appeared to have aged more quickly — by 15 years on average — than a person’s actual age. That’s unusual, because older people with colorectal cancer don’t have the same boost in cellular aging.

The rate of colorectal cancer among young people has been rising at an alarming rate, according to a 2023 report from the American Cancer Society. In 2019, one in five colorectal cancer cases were among people younger than 55. That’s up from 1 in 10 in 1995, which means the rate has doubled in less than 30 years.
 

Need Colon Cancer Screening?

Who needs a colorectal cancer screening? Ask colorectal cancer specialist Nancy Kemeny, MD.

A 2017 analysis estimated that a person’s risk of colorectal cancer increased 12% by eating 3.5 ounces of red or processed meat daily, which is the equivalent of the size of a deck of playing cards. The same study also linked colorectal cancer risk to alcohol intake, citing its ethanol content. Eating a diet high in fiber can reduce a person’s risk.

This latest study aligned with previous findings that link bacteria called Fusobacterium to colorectal cancer. It’s not unusual for Fusobacterium to be present in a person’s mouth, but it is more likely to be found in the intestines of colorectal cancer patients, compared with those of healthy people. One study even found that people with colorectal cancer were five times more likely to have Fusobacterium in their stool, compared with healthy people.

Colorectal cancer is more common among men than women, “likely reflecting differences in risk factor prevalence, such as excess body weight and processed meat consumption,” the authors of the 2023 American Cancer Society report explained.

People younger than 45 should alert their medical provider if they have constipation, rectal bleeding, or sudden changes in bowel movements, which can be symptoms of colorectal cancer. Screening for colorectal cancer should begin for most people at age 45.

A version of this article appeared on WebMD.com.

CHICAGO — Genetics and diet have been among the top theories for what may be fueling the troubling rise of colorectal cancer in young adults. Now, an early look at genetic data from people with colorectal cancer further suggests that the cause is linked to what is happening in the gut.

The findings were presented at the annual meeting of the American Society for Clinical Oncology (ASCO) by researchers from Ohio State University. For the analysis, they analyzed genetic data on tumors.

The researchers found signs that a high-fat, low-fiber diet may increase inflammation in the gut that prevents it from naturally suppressing tumors. The cells of young people with colorectal cancer also appeared to have aged more quickly — by 15 years on average — than a person’s actual age. That’s unusual, because older people with colorectal cancer don’t have the same boost in cellular aging.

The rate of colorectal cancer among young people has been rising at an alarming rate, according to a 2023 report from the American Cancer Society. In 2019, one in five colorectal cancer cases were among people younger than 55. That’s up from 1 in 10 in 1995, which means the rate has doubled in less than 30 years.
 

Need Colon Cancer Screening?

Who needs a colorectal cancer screening? Ask colorectal cancer specialist Nancy Kemeny, MD.

A 2017 analysis estimated that a person’s risk of colorectal cancer increased 12% by eating 3.5 ounces of red or processed meat daily, which is the equivalent of the size of a deck of playing cards. The same study also linked colorectal cancer risk to alcohol intake, citing its ethanol content. Eating a diet high in fiber can reduce a person’s risk.

This latest study aligned with previous findings that link bacteria called Fusobacterium to colorectal cancer. It’s not unusual for Fusobacterium to be present in a person’s mouth, but it is more likely to be found in the intestines of colorectal cancer patients, compared with those of healthy people. One study even found that people with colorectal cancer were five times more likely to have Fusobacterium in their stool, compared with healthy people.

Colorectal cancer is more common among men than women, “likely reflecting differences in risk factor prevalence, such as excess body weight and processed meat consumption,” the authors of the 2023 American Cancer Society report explained.

People younger than 45 should alert their medical provider if they have constipation, rectal bleeding, or sudden changes in bowel movements, which can be symptoms of colorectal cancer. Screening for colorectal cancer should begin for most people at age 45.

A version of this article appeared on WebMD.com.

TOPLINE:

Patients with early-onset colorectal cancer (EOCRC) often present with hematochezia or abdominal pain, symptoms frequently overlooked in younger populations, leading to delays in diagnosis of 4-6 months, a new analysis showed.

METHODOLOGY:

• As the number of cases of EOCRC, defined as colorectal cancer (CRC) diagnosed before age 50, continues to rise, early detection has become increasingly important. Improved recognition of presenting signs and symptoms associated with EOCRC could lead to a more timely diagnosis and better clinical outcomes.
• In a systematic review and meta-analysis of 81 studies with 24.9 million EOCRC cases, researchers sought to determine the most common presenting signs and symptoms, their association with EOCRC risk, and the time from presentation to diagnosis.
• Data extraction and quality assessment were performed independently in duplicate using PRISMA guidelines, and Joanna Briggs Institute critical appraisal tools were used to measure the risk of bias.

TAKEAWAY:

• Hematochezia was the most common presenting sign/symptom, with a pooled prevalence of 45%, followed by abdominal pain, with a pooled prevalence of 40%.
• Altered bowel habits, which included constipation, diarrhea, and alternating bowel habits, were the third most common presenting sign/symptom (pooled prevalence of 27%), followed by unexplained weight loss (pooled prevalence of 17%).
• The likelihood of EOCRC was estimated to be fivefold to 54-fold higher with hematochezia and 1.3-fold to sixfold higher with abdominal pain.
• The mean time from sign or symptom onset to EOCRC diagnosis was 6.4 months (range, 1.8-13.7 months).

IN PRACTICE:

“These findings and the increasing risk of CRC in individuals younger than 50 years highlight the urgent need to educate clinicians and patients about these signs and symptoms to ensure that diagnostic workup and resolution are not delayed. Adapting current clinical practice to identify and address these signs and symptoms through careful clinical triage and follow-up could help limit morbidity and mortality associated with EOCRC,” the authors wrote.

SOURCE:

The study, with Joshua Demb, PhD, MPH, division of gastroenterology, department of medicine, University of California, San Diego, was published online May 24 in JAMA Network Open.

LIMITATIONS:

Significant heterogeneity across studies affected the ability to meta-analyze some results. The cross-sectional data limited the ability to stratify by age, sex, race and ethnicity, or genetic ancestry. It was not possible to evaluate the impact of time to diagnosis on CRC outcomes due to a limited number of studies answering this question. Researchers were unable to examine the constellation of signs and symptoms because they lacked individual-level data from each study.

DISCLOSURES:

The authors disclosed no relevant conflicts of interest. No specific funding was disclosed.
 

A version of this article appeared on Medscape.com.

TOPLINE:

Patients with early-onset colorectal cancer (EOCRC) often present with hematochezia or abdominal pain, symptoms frequently overlooked in younger populations, leading to delays in diagnosis of 4-6 months, a new analysis showed.

METHODOLOGY:

• As the number of cases of EOCRC, defined as colorectal cancer (CRC) diagnosed before age 50, continues to rise, early detection has become increasingly important. Improved recognition of presenting signs and symptoms associated with EOCRC could lead to a more timely diagnosis and better clinical outcomes.
• In a systematic review and meta-analysis of 81 studies with 24.9 million EOCRC cases, researchers sought to determine the most common presenting signs and symptoms, their association with EOCRC risk, and the time from presentation to diagnosis.
• Data extraction and quality assessment were performed independently in duplicate using PRISMA guidelines, and Joanna Briggs Institute critical appraisal tools were used to measure the risk of bias.

TAKEAWAY:

• Hematochezia was the most common presenting sign/symptom, with a pooled prevalence of 45%, followed by abdominal pain, with a pooled prevalence of 40%.
• Altered bowel habits, which included constipation, diarrhea, and alternating bowel habits, were the third most common presenting sign/symptom (pooled prevalence of 27%), followed by unexplained weight loss (pooled prevalence of 17%).
• The likelihood of EOCRC was estimated to be fivefold to 54-fold higher with hematochezia and 1.3-fold to sixfold higher with abdominal pain.
• The mean time from sign or symptom onset to EOCRC diagnosis was 6.4 months (range, 1.8-13.7 months).

IN PRACTICE:

“These findings and the increasing risk of CRC in individuals younger than 50 years highlight the urgent need to educate clinicians and patients about these signs and symptoms to ensure that diagnostic workup and resolution are not delayed. Adapting current clinical practice to identify and address these signs and symptoms through careful clinical triage and follow-up could help limit morbidity and mortality associated with EOCRC,” the authors wrote.

SOURCE:

The study, with Joshua Demb, PhD, MPH, division of gastroenterology, department of medicine, University of California, San Diego, was published online May 24 in JAMA Network Open.

LIMITATIONS:

Significant heterogeneity across studies affected the ability to meta-analyze some results. The cross-sectional data limited the ability to stratify by age, sex, race and ethnicity, or genetic ancestry. It was not possible to evaluate the impact of time to diagnosis on CRC outcomes due to a limited number of studies answering this question. Researchers were unable to examine the constellation of signs and symptoms because they lacked individual-level data from each study.

DISCLOSURES:

The authors disclosed no relevant conflicts of interest. No specific funding was disclosed.
 

A version of this article appeared on Medscape.com.

TOPLINE:

Patients with early-onset colorectal cancer (EOCRC) often present with hematochezia or abdominal pain, symptoms frequently overlooked in younger populations, leading to delays in diagnosis of 4-6 months, a new analysis showed.

METHODOLOGY:

• As the number of cases of EOCRC, defined as colorectal cancer (CRC) diagnosed before age 50, continues to rise, early detection has become increasingly important. Improved recognition of presenting signs and symptoms associated with EOCRC could lead to a more timely diagnosis and better clinical outcomes.
• In a systematic review and meta-analysis of 81 studies with 24.9 million EOCRC cases, researchers sought to determine the most common presenting signs and symptoms, their association with EOCRC risk, and the time from presentation to diagnosis.
• Data extraction and quality assessment were performed independently in duplicate using PRISMA guidelines, and Joanna Briggs Institute critical appraisal tools were used to measure the risk of bias.

TAKEAWAY:

• Hematochezia was the most common presenting sign/symptom, with a pooled prevalence of 45%, followed by abdominal pain, with a pooled prevalence of 40%.
• Altered bowel habits, which included constipation, diarrhea, and alternating bowel habits, were the third most common presenting sign/symptom (pooled prevalence of 27%), followed by unexplained weight loss (pooled prevalence of 17%).
• The likelihood of EOCRC was estimated to be fivefold to 54-fold higher with hematochezia and 1.3-fold to sixfold higher with abdominal pain.
• The mean time from sign or symptom onset to EOCRC diagnosis was 6.4 months (range, 1.8-13.7 months).

IN PRACTICE:

“These findings and the increasing risk of CRC in individuals younger than 50 years highlight the urgent need to educate clinicians and patients about these signs and symptoms to ensure that diagnostic workup and resolution are not delayed. Adapting current clinical practice to identify and address these signs and symptoms through careful clinical triage and follow-up could help limit morbidity and mortality associated with EOCRC,” the authors wrote.

SOURCE:

The study, with Joshua Demb, PhD, MPH, division of gastroenterology, department of medicine, University of California, San Diego, was published online May 24 in JAMA Network Open.

LIMITATIONS:

Significant heterogeneity across studies affected the ability to meta-analyze some results. The cross-sectional data limited the ability to stratify by age, sex, race and ethnicity, or genetic ancestry. It was not possible to evaluate the impact of time to diagnosis on CRC outcomes due to a limited number of studies answering this question. Researchers were unable to examine the constellation of signs and symptoms because they lacked individual-level data from each study.

DISCLOSURES:

The authors disclosed no relevant conflicts of interest. No specific funding was disclosed.
 

A version of this article appeared on Medscape.com.

WASHINGTON — Eating within 3 hours of bedtime at least 4 days a week could increase chances for developing colorectal cancer, according to the results of research presented at the annual Digestive Disease Week^® (DDW).

Investigators in a new study questioned 664 people getting a colonoscopy to screen for cancer, and 42% said they were late eaters. This group was 46% more likely than non–late eaters to have an adenoma found during colonoscopy. An estimated 5% to 10% of them become cancerous over time.

“A lot of other studies are about what we eat but not when we eat,” said Edena Khoshaba, lead investigator and a medical student at Rush University Medical College in Chicago. “The common advice includes not eating red meat, eating more fruits and vegetables — which is great, of course — but we wanted to see if the timing affects us at all.”

Ms. Khoshaba and colleagues found it did. Late eaters were 5.5 times more likely to have three or more tubular adenomas compared to non–late eaters, even after adjusting for what people were eating. Tubular adenomas are the most common type of polyp found in the colon.

So, what’s the possible connection between late eating and the risk for colorectal cancer?
 

Resetting Your Internal Clock

Eating close to bedtime could be throwing off the body’s circadian rhythm. But in this case, it’s not the central circadian center located in the brain — the one that releases melatonin. Instead, late eating could disrupt the peripheral circadian rhythm, part of which is found in the GI tract. For example, if a person is eating late at night, the brain thinks it is nighttime while the gut thinks it is daytime, Ms. Khoshaba said in an interview.

This is an interesting study, said Amy Bragagnini, MS, RD, spokesperson for the Academy of Nutrition and Dietetics, when asked to comment on the research. “It is true that eating later at night can disrupt your circadian rhythm.”

“In addition, many of my patients have told me that when they do eat later at night, they don’t always make the healthiest food choices,” Ms. Bragagnini said. “Their late-night food choices are generally higher in added sugar and fat. This may cause them to consume far more calories than their body needs.” So, eating late at night can also lead to unwanted weight gain.

An unanswered question is if late eating is connected in any way at all to increasing rates of colorectal cancer seen in younger patients.

This was an observational study, and another possible limitation, Ms. Khoshaba said, is that people were asked to recall their diets over 24 hours, which may not always be accurate.

Some of the organisms in the gut have their own internal clocks that follow a daily rhythm, and what someone eat determines how many different kinds of these organisms are active, Ms. Bragagnini said.

“So, if your late-night eating consists of foods high in sugar and fat, you may be negatively impacting your microbiome.” she said.

The next step for Ms. Khoshaba and colleagues is a study examining the peripheral circadian rhythm, changes in the gut microbiome, and the risk for developing metabolic syndrome. Ms. Khoshaba and Ms. Bragagnini had no relevant disclosures.

A version of this article appeared on Medscape.com.

WASHINGTON — Eating within 3 hours of bedtime at least 4 days a week could increase chances for developing colorectal cancer, according to the results of research presented at the annual Digestive Disease Week^® (DDW).

Investigators in a new study questioned 664 people getting a colonoscopy to screen for cancer, and 42% said they were late eaters. This group was 46% more likely than non–late eaters to have an adenoma found during colonoscopy. An estimated 5% to 10% of them become cancerous over time.

“A lot of other studies are about what we eat but not when we eat,” said Edena Khoshaba, lead investigator and a medical student at Rush University Medical College in Chicago. “The common advice includes not eating red meat, eating more fruits and vegetables — which is great, of course — but we wanted to see if the timing affects us at all.”

Ms. Khoshaba and colleagues found it did. Late eaters were 5.5 times more likely to have three or more tubular adenomas compared to non–late eaters, even after adjusting for what people were eating. Tubular adenomas are the most common type of polyp found in the colon.

So, what’s the possible connection between late eating and the risk for colorectal cancer?
 

Resetting Your Internal Clock

Eating close to bedtime could be throwing off the body’s circadian rhythm. But in this case, it’s not the central circadian center located in the brain — the one that releases melatonin. Instead, late eating could disrupt the peripheral circadian rhythm, part of which is found in the GI tract. For example, if a person is eating late at night, the brain thinks it is nighttime while the gut thinks it is daytime, Ms. Khoshaba said in an interview.

This is an interesting study, said Amy Bragagnini, MS, RD, spokesperson for the Academy of Nutrition and Dietetics, when asked to comment on the research. “It is true that eating later at night can disrupt your circadian rhythm.”

“In addition, many of my patients have told me that when they do eat later at night, they don’t always make the healthiest food choices,” Ms. Bragagnini said. “Their late-night food choices are generally higher in added sugar and fat. This may cause them to consume far more calories than their body needs.” So, eating late at night can also lead to unwanted weight gain.

An unanswered question is if late eating is connected in any way at all to increasing rates of colorectal cancer seen in younger patients.

This was an observational study, and another possible limitation, Ms. Khoshaba said, is that people were asked to recall their diets over 24 hours, which may not always be accurate.

Some of the organisms in the gut have their own internal clocks that follow a daily rhythm, and what someone eat determines how many different kinds of these organisms are active, Ms. Bragagnini said.

“So, if your late-night eating consists of foods high in sugar and fat, you may be negatively impacting your microbiome.” she said.

The next step for Ms. Khoshaba and colleagues is a study examining the peripheral circadian rhythm, changes in the gut microbiome, and the risk for developing metabolic syndrome. Ms. Khoshaba and Ms. Bragagnini had no relevant disclosures.

A version of this article appeared on Medscape.com.

WASHINGTON — Eating within 3 hours of bedtime at least 4 days a week could increase chances for developing colorectal cancer, according to the results of research presented at the annual Digestive Disease Week^® (DDW).

Investigators in a new study questioned 664 people getting a colonoscopy to screen for cancer, and 42% said they were late eaters. This group was 46% more likely than non–late eaters to have an adenoma found during colonoscopy. An estimated 5% to 10% of them become cancerous over time.

“A lot of other studies are about what we eat but not when we eat,” said Edena Khoshaba, lead investigator and a medical student at Rush University Medical College in Chicago. “The common advice includes not eating red meat, eating more fruits and vegetables — which is great, of course — but we wanted to see if the timing affects us at all.”

Ms. Khoshaba and colleagues found it did. Late eaters were 5.5 times more likely to have three or more tubular adenomas compared to non–late eaters, even after adjusting for what people were eating. Tubular adenomas are the most common type of polyp found in the colon.

So, what’s the possible connection between late eating and the risk for colorectal cancer?
 

Resetting Your Internal Clock

Eating close to bedtime could be throwing off the body’s circadian rhythm. But in this case, it’s not the central circadian center located in the brain — the one that releases melatonin. Instead, late eating could disrupt the peripheral circadian rhythm, part of which is found in the GI tract. For example, if a person is eating late at night, the brain thinks it is nighttime while the gut thinks it is daytime, Ms. Khoshaba said in an interview.

This is an interesting study, said Amy Bragagnini, MS, RD, spokesperson for the Academy of Nutrition and Dietetics, when asked to comment on the research. “It is true that eating later at night can disrupt your circadian rhythm.”

“In addition, many of my patients have told me that when they do eat later at night, they don’t always make the healthiest food choices,” Ms. Bragagnini said. “Their late-night food choices are generally higher in added sugar and fat. This may cause them to consume far more calories than their body needs.” So, eating late at night can also lead to unwanted weight gain.

An unanswered question is if late eating is connected in any way at all to increasing rates of colorectal cancer seen in younger patients.

This was an observational study, and another possible limitation, Ms. Khoshaba said, is that people were asked to recall their diets over 24 hours, which may not always be accurate.

Some of the organisms in the gut have their own internal clocks that follow a daily rhythm, and what someone eat determines how many different kinds of these organisms are active, Ms. Bragagnini said.

“So, if your late-night eating consists of foods high in sugar and fat, you may be negatively impacting your microbiome.” she said.

The next step for Ms. Khoshaba and colleagues is a study examining the peripheral circadian rhythm, changes in the gut microbiome, and the risk for developing metabolic syndrome. Ms. Khoshaba and Ms. Bragagnini had no relevant disclosures.

A version of this article appeared on Medscape.com.

TOPLINE:

The recommended 10-year interval between screening colonoscopies may be safely extended to 15 years in adults with no family history of colorectal cancer (CRC) whose first colonoscopy is negative for CRC, a population-based study suggests.

METHODOLOGY:

• Using Swedish nationwide registry data, researchers compared 110,074 individuals who had a first colonoscopy with negative findings for CRC at age 45-69 years (exposed group) with more than 1.9 million matched controls who either did not have a colonoscopy during the study period or underwent colonoscopy that led to a CRC diagnosis.
• They calculated 10-year standardized incidence ratio (SIR) and standardized mortality ratio (SMR) to compare risks for CRC and CRC-specific death in the exposed and control groups based on different follow-up screening intervals.

TAKEAWAY:

• During up to 29 years of follow-up, 484 incident CRCs and 112 CRC deaths occurred in the group with a negative initial colonoscopy.
• Up to 15 years after negative colonoscopy, the 10-year cumulative risk for CRC and CRC mortality was lower than in the control group, with an SIR of 0.72 and SMR of 0.55, respectively.
• Extending the screening interval from 10 to 15 years would miss early detection of only two CRC cases and prevention of only one CRC death per 1000 individuals, while potentially avoiding 1000 colonoscopies.

IN PRACTICE:

“This study provides evidence for recommending a longer colonoscopy screening interval than what is currently recommended in most guidelines for populations with no familial risk of CRC,” the authors wrote. “A longer interval between colonoscopy screenings could be beneficial in avoiding unnecessary invasive examinations.”

SOURCE:

The study, with first author Qunfeng Liang, MSc, with the German Cancer Research Center, Heidelberg, Germany, was published online on May 2 in JAMA Oncology.

LIMITATIONS:

The study population primarily included White individuals, particularly ethnic Swedish individuals, so external validation would be necessary to generalize the recommendation to other populations. The researchers lacked data on non-endoscopic tests, such as fecal occult blood tests, which could have been performed as a substitution for colonoscopy during the interval between colonoscopy screenings.

DISCLOSURES:

The study had no specific funding. The authors had no relevant conflicts of interest.

A version of this article appeared on Medscape.com.

TOPLINE:

The recommended 10-year interval between screening colonoscopies may be safely extended to 15 years in adults with no family history of colorectal cancer (CRC) whose first colonoscopy is negative for CRC, a population-based study suggests.

METHODOLOGY:

• Using Swedish nationwide registry data, researchers compared 110,074 individuals who had a first colonoscopy with negative findings for CRC at age 45-69 years (exposed group) with more than 1.9 million matched controls who either did not have a colonoscopy during the study period or underwent colonoscopy that led to a CRC diagnosis.
• They calculated 10-year standardized incidence ratio (SIR) and standardized mortality ratio (SMR) to compare risks for CRC and CRC-specific death in the exposed and control groups based on different follow-up screening intervals.

TAKEAWAY:

• During up to 29 years of follow-up, 484 incident CRCs and 112 CRC deaths occurred in the group with a negative initial colonoscopy.
• Up to 15 years after negative colonoscopy, the 10-year cumulative risk for CRC and CRC mortality was lower than in the control group, with an SIR of 0.72 and SMR of 0.55, respectively.
• Extending the screening interval from 10 to 15 years would miss early detection of only two CRC cases and prevention of only one CRC death per 1000 individuals, while potentially avoiding 1000 colonoscopies.

IN PRACTICE:

“This study provides evidence for recommending a longer colonoscopy screening interval than what is currently recommended in most guidelines for populations with no familial risk of CRC,” the authors wrote. “A longer interval between colonoscopy screenings could be beneficial in avoiding unnecessary invasive examinations.”

SOURCE:

The study, with first author Qunfeng Liang, MSc, with the German Cancer Research Center, Heidelberg, Germany, was published online on May 2 in JAMA Oncology.

LIMITATIONS:

The study population primarily included White individuals, particularly ethnic Swedish individuals, so external validation would be necessary to generalize the recommendation to other populations. The researchers lacked data on non-endoscopic tests, such as fecal occult blood tests, which could have been performed as a substitution for colonoscopy during the interval between colonoscopy screenings.

DISCLOSURES:

The study had no specific funding. The authors had no relevant conflicts of interest.

A version of this article appeared on Medscape.com.

TOPLINE:

The recommended 10-year interval between screening colonoscopies may be safely extended to 15 years in adults with no family history of colorectal cancer (CRC) whose first colonoscopy is negative for CRC, a population-based study suggests.

METHODOLOGY:

• Using Swedish nationwide registry data, researchers compared 110,074 individuals who had a first colonoscopy with negative findings for CRC at age 45-69 years (exposed group) with more than 1.9 million matched controls who either did not have a colonoscopy during the study period or underwent colonoscopy that led to a CRC diagnosis.
• They calculated 10-year standardized incidence ratio (SIR) and standardized mortality ratio (SMR) to compare risks for CRC and CRC-specific death in the exposed and control groups based on different follow-up screening intervals.

TAKEAWAY:

• During up to 29 years of follow-up, 484 incident CRCs and 112 CRC deaths occurred in the group with a negative initial colonoscopy.
• Up to 15 years after negative colonoscopy, the 10-year cumulative risk for CRC and CRC mortality was lower than in the control group, with an SIR of 0.72 and SMR of 0.55, respectively.
• Extending the screening interval from 10 to 15 years would miss early detection of only two CRC cases and prevention of only one CRC death per 1000 individuals, while potentially avoiding 1000 colonoscopies.

IN PRACTICE:

“This study provides evidence for recommending a longer colonoscopy screening interval than what is currently recommended in most guidelines for populations with no familial risk of CRC,” the authors wrote. “A longer interval between colonoscopy screenings could be beneficial in avoiding unnecessary invasive examinations.”

SOURCE:

The study, with first author Qunfeng Liang, MSc, with the German Cancer Research Center, Heidelberg, Germany, was published online on May 2 in JAMA Oncology.

LIMITATIONS:

The study population primarily included White individuals, particularly ethnic Swedish individuals, so external validation would be necessary to generalize the recommendation to other populations. The researchers lacked data on non-endoscopic tests, such as fecal occult blood tests, which could have been performed as a substitution for colonoscopy during the interval between colonoscopy screenings.

DISCLOSURES:

The study had no specific funding. The authors had no relevant conflicts of interest.

A version of this article appeared on Medscape.com.