CRC screening recommendations for average-risk and high-risk persons from US GI societies

Reference

Rex DK, Boland CR, Dominitz JA, et al. Colorectal cancer screening: recommendations for physicians and patients from the U.S. Multi-Society Task Force on Colorectal Cancer. Am J Gastroenterol 2017;112(7):1016-1030.

Synopsis

This guideline took a semi-evidence–based approach: Although the authors state that they carefully searched PubMed and other databases, there is no evidence of an analytic framework; they did not do their own systematic review; and the process for arriving at the strength of recommendations is not very explicit, other than stating that a consensus process was used. That said, their main recommendations are similar to those of the USPSTF: offer screening beginning at age 50 years (those with previous negative screening results should consider stopping at age 75) with colonoscopy every 10 years or fecal immunochemical test (FIT) annually as the preferred Tier 1 options. They list CT colonography every 5 years, FIT plus fecal DNA (ie, Cologuard) every 3 years, or flexible sigmoidoscopy every 5 to 10 years as Tier 2 options. This is a sensible tiering based on the harms, benefits, and costs: FIT and colonoscopy provide the best balance of benefit and harm, with FIT having lower cost and harm, and colonoscopy having a bit more benefit but also more harm and cost, based on USPSTF-sponsored modeling studies. They also recommend that physicians monitor the quality of screening, for example by looking at yield and complication rates. The primary value of the guideline is in that it makes recommendations (albeit based largely on expert opinion and observational data) regarding screening for high-risk groups. For patients with familial colorectal cancer syndrome X, they recommend colonoscopy every 3 to 5 years, beginning 10 years before the age at diagnosis of the youngest relative. For patients with colorectal cancer or advanced adenoma in a single first-degree relative diagnosed at 60 years or older, they recommend screening with the usual tests and intervals but beginning at 40 years of age. For those with colorectal cancer or advanced adenoma in 2 first-degree relatives or in one relative younger than 60 years, they recommend perform colonoscopy every 5 years beginning no later than age 40 or 10 years before the first diagnosis (whichever comes first). They also recommend that screening begin at age 45 years for African-American patients. Note, though, that the authors describe these as weak recommendations with very-low-quality evidence. Although it seems that modeling could help answer the question of screening in high-risk groups, they do not cite any modeling studies.