issued by the American College of Physicians.
Regular screening can be discontinued after age 75 years, Amir Qaseem, MD, president of clinical policy and the Center for Evidence Reviews at the American College of Physicians, and colleagues wrote in the Annals of Internal Medicine.
No one test is preferred over another, according to the guidance statement. Patients and physicians can select the test type together, based on individual needs and preferences, and each test carries its own screening interval. But regular testing has been proven time and again to reduce the risk of colorectal cancer mortality, and more people should have it, according to the guidance.
“Not enough people in the United States get screened for colorectal cancer,” ACP President Robert M. McLean, MD, said in a press statement. “Physicians should perform an individualized risk assessment for colorectal cancer in all adults. Doctors and patients should select the screening test based on a discussion of the benefits, harms, costs, availability, frequency, and patient preferences.”
The guidance is an attempt to balance existing guidelines authored by the U.S. Preventive Services Task Force and the Canadian Task Force on Preventive Health Care (CTFPHC), but it also was developed following critical review of those from the American Cancer Society and other organizations.
The ACP guidance is for adults at average risk for colorectal cancer who do not have symptoms; it does not apply to adults with a family history of colorectal cancer, a long-standing history of inflammatory bowel disease, genetic syndromes such as familial cancerous polyps, a personal history of previous colorectal cancer or benign polyps, or other risk factors.
The guidance was based on evaluations of stool-based tests, including the fecal immunochemical test (FIT), also called the immunochemical-based fecal occult blood test (FOBT), and direct visualization with endoscopic and radiologic tests, including flexible sigmoidoscopy, colonoscopy, and CT colonography. The guidance includes the following recommendations:
Clinicians should regularly screen for colorectal cancer in average-risk adults between the ages of 50 and 75 years.
This recommendation is in line with those made by the U.S. Preventive Services Task Force and the CTFPHC. Data suggest that regular screening reduces colorectal cancer–specific mortality in this age group, with those aged 65-75 years likely to garner the most benefit.
The absolute risk reduction increases with age and varies with test type. For every-other-year FOBT, it rises from 0.037% in those younger than 60 years to 0.20% in those aged 60 years or older. For flexible sigmoidoscopy, the risk reduction rises from 0.05% in the younger group to 0.29% in the older group.
Data from the CTFPHC show that the net benefit in those aged 50-59 years is small, however. This may influence the decision about when to start screening.
Clinicians should select the colorectal cancer screening test with the patient based on a discussion of benefits, harms, costs, availability, frequency, and patient preferences.
The FIT or FOBT should be performed every 2 years, colonoscopy every 10 years, and flexible sigmoidoscopy every 10 years, plus FIT every 2 years.
No data suggest a benefit of one test over another; however, “all screening tests are associated with potential benefits as well as harms,” the document states. “Clinical decisions need to be individualized using patient clinical characteristics, patient preferences, and screening test frequency and availability. Because many eligible patients have never been screened and some may not adhere to recommendations about subsequent screening or follow-up of positive findings on screening tests (such as colonoscopy after a positive result on a stool-based screening test), patient informed decision making and adherence are important factors in selection of a [colorectal cancer] screening test.”
Discussions with patients should include topics like the recommended frequency of each test, bowel preparation, anesthesia, transportation to and from testing site, time commitments, and the necessary steps if a test result is positive.
