Long-Term CRC Risk Is Elevated in Patients with Large Serrated Polyps

Serrated lesions are considered precursors of hypermethylated colorectal cancers (CRCs), but the long-term risk for CRC in patients with serrated polyps is not understood.

In a population-based trial in Norway, 12,955 participants underwent flexible sigmoidoscopy between 1999 and 2001. In 2012, participants with serrated polyps detected who had not had follow-up were offered repeat colonoscopy.

Of 103 individuals (0.8%) with ≥1 large (≥10 mm) serrated polyps at flexible sigmoidoscopy, 22 had a concomitant advanced adenoma, leaving 81 patients in the serrated polyp group, among whom 450 polyps were detected (51 nonadvanced adenomas and 399 serrated polyps). Histologic reevaluation confirmed these as hyperplastic polyp (35%), sessile serrated a…