Metachronous CRC risk after colonoscopy for positive FIT

TOPLINE:

Adults with high-risk serrated polyps (with or without high-risk adenomas) have a high risk for metachronous colorectal cancer (CRC) within a median of 3 years after the baseline colonoscopy for a positive fecal immunochemical test (FIT) screen, a study suggests.

,

METHODOLOGY:

• Investigators conducted a retrospective analysis of 253,833 colonoscopies performed after FIT-positive screens in a Dutch CRC screening program.
• A Cox regression analysis assessed the association between the findings at baseline colonoscopy and metachronous CRC risk.
• Investigators categorized patients into subgroups based on removed polyp subtypes and used groups without polyps as a reference.
• High-risk subgroups included those with high-risk serrated polyps, which were defined as a serrated polyp of at least 10 mm, sessile serrated lesions with dysplasia, or traditional serrated adenomas, as well as high-risk adenomas, which were defined as an adenoma of at least 10 mm or containing high-grade dysplasia.

TAKEAWAY:

• Over a median follow-up of 36 months, 504 metachronous CRCs were identified.
• Individuals with high-risk serrated polyps without co-occurring high-risk adenomas had an increased risk for metachronous CRC (hazard ratio, 1.70).
• The highest risk was seen in individuals with both high-risk serrated polyps and high-risk adenomas (HR, 2.0), as well as those with villous adenomas (HR, 2.07).
• Individuals with only high-risk adenomas did not show a significantly increased risk for metachronous CRC (HR, 1.22).

IN PRACTICE:

“Our results suggest that individuals with high-risk serrated polyps might comprise the higher CRC risk in the first years after colonoscopy. Results of this study could contribute to establish more restrictive polyp surveillance guidelines in a quality-assured setting,” the authors wrote.

SOURCE:

The study was led by David E. F. W. M. van Toledo, MD, department of gastroenterology and hepatology, Amsterdam University Medical Centers. It was published online July 5, 2023, in eClinicalMedicine. The study received no funding.

LIMITATIONS:

The relatively short median follow-up time of 3 years may limit the assessment of long-term metachronous CRC risk. The study population consisted of FIT-positive individuals, which may introduce selection bias. The incidence of metachronous CRC in the study was lower compared with other studies, potentially affecting the risk estimates. The limited number of cases in some subgroups may result in unreliable risk estimations.

DISCLOSURES:

Dr. van Toledo declared no relevant financial relationships.

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