Colonoscopy Delay After Positive Fecal Screen Linked With Worse Cancer Outcomes

A longer time lag between a positive fecal screening test and colonoscopy is associated with worse colorectal cancer outcomes, according to a systematic review published in Clinical Gastroenterology and Hepatology.

“In this systematic review, we observed clear associations between longer time delay to colonoscopy after positive fecal-based colorectal cancer screening testing and increased incidence of colorectal cancer, more advanced cancer stage at diagnosis, and higher colorectal cancer-specific mortality,” researchers reported.

The systematic review included 8 studies, 5 of which reported outcomes for fecal immunochemical testing.

“Although meta-analysis was not possible, consistent trends between longer time delays and worse outcomes were apparent in all studies,” researchers wrote.

Compared with colonoscopy performed within 1 month of positive fecal immunochemical testing, colonoscopy beyond 9 months was significantly linked with increased incidence of colorectal cancer. The two largest studies in the review reported adjusted odds ratios of 1.75 and 1.48.

Colonoscopy performed after 9 months was also significantly associated with higher incidence of advanced-stage colorectal cancer at diagnosis. Adjusted odds ratios were 2.79 and 1.55 in the 2 largest studies.

The single study that assessed colorectal cancer-specific mortality reported a hazard ratio of 1.53 with colonoscopy after 12 months, researchers reported.

“Further research is urgently needed to elucidate the optimal time frame within which those with positive fecal testing should undergo colonoscopy. However, it is clear even now that incident colorectal cancer and advanced-stage colorectal cancer are both higher beyond 9 months,” researchers concluded. “Thus, it is incumbent on practitioners and the health system to support completion of colonoscopy well in advance of this time point.”

—Jolynn Tumolo

Reference

Forbes N, Hilsden RJ, Martel M, et al. Association between time to colonoscopy after positive fecal testing and colorectal cancer outcomes: a systematic review. Clin Gastroenterol Hepatol 2021;19(7):1344-1354.e8.