Serrated Lesions Are Not a Major Factor in Lynch Syndrome

Cancers in Lynch syndrome are generally assumed to go through the conventional adenoma-to-carcinoma development sequence, but there has been speculation as to whether the serrated pathway plays a role. To investigate this hypothesis, investigators in the Netherlands retrospectively examined results from colonoscopies in 223 patients with Lynch syndrome and 223 controls exactly matched for age, gender, and indication. Resected lesions were re-reviewed by pathology experts who were blinded to disease status.

The prevalence of sessile serrated polyps was 7.6% in patients with Lynch syndrome and 6.7% in controls (P=0.86), and no sessile serrated polyp found in Lynch patients was dysplastic.