Baseline Screening Colonoscopy and 10-Year Risk for Advanced Neoplasia

Individuals at average risk for colorectal cancer with 1 or 2 small (<10 mm) colorectal adenomas are thought to be at low risk for developing advanced colorectal neoplasia (ACRN; adenomas ≥10 mm, adenomas with villous history or high-grade dysplasia, or colorectal cancer). But longitudinal data from large screening colonoscopy cohorts have been lacking.

The current study reports the 10-year risk of ACRN among 3121 patients receiving baseline screening colonoscopy at 1 of 13 VA medical centers between 1994 and 1997. Surveillance was per study protocol for 5 years and per usual care subsequently. Of 1915 individuals with ≥1 surveillance colonoscopy, 146 developed ACRN over 10 years. Results by baseline findings were as follows:

• The cumulative 1…