Does the time of follow-up colonoscopy after a positive fecal immunochemical test affect the risk of colon cancer and more advanced-stage disease?

In adults with a positive fecal immunochemical test (FIT) result, there are no differences in colorectal cancer outcomes if the follow-up colon examination occurs within 6 months. Follow-up colon examination from 6 months to 10 months is associated with an increased risk of stage II colorectal cancer. Follow-up after 10 months is significantly associated with an increased risk of advanced-stage disease, including stage IV colorectal cancer. (LOE = 2b)

Corley DA, Jensen CD, Quinn VP, et al. Association between time to colonoscopy after a positive fecal test result and risk of colorectal cancer and cancer stage at diagnosis. JAMA 2017;317(16):1631-1641.  [PMID:28444278]

Cohort (retrospective)

Government

Population-based

These invesigators retrospectively analyzed data obtained from a large health care system in California on adults, aged 50 to 75 years, with a positive screening FIT result and a subsequent referral for colonoscopy scheduling. Exclusion criteria included a history of colon cancer, less than a year of membership in the system and no record of a colonoscopy since enrollment, a colonoscopy within less than 10 years or sigmoidoscopy within less than 5 years, and colonoscopy or colorectal cancer diagnosis within 1 to 7 days after the positive FIT result. Of the eligible participants with a positive FIT result (N = 81,518), 86% received a follow-up colonoscopy. Of these 33.3% received a colonoscopy within 30 days, 63.6% within 2 months, 74.2% within 3 months, 80.6% within 6 months, and 83.2% within 12 months. No significant differences occurred in the risk of colorectal cancer with follow-up colonoscopy within 6 months compared with follow-up between 8 days and 30 days. For those patients with follow-up from 7 months to 9 months, the risk of stage II colorectal cancer was significantly increased compared with the patients with follow-up in less than 30 days (12 vs 9 cases per 1000 patients). For follow-up colonoscopy at 10 months to 12 months the risk of any colorectal cancer was significantly increased (49 cases per 1000 patients), as was advanced-stage disease (19 cases per 1000 patients) and stage IV colorectal cancer (7 cases per 1000 patients). Risks were even more significantly increased with follow-up examinations more than 12 months after initial FIT.