Lesions Are Flatter in Lynch Syndrome

The polyp-to-cancer sequence occurs on average more quickly in Lynch syndrome than in sporadic cancers. Loss of mismatch repair, which can lead to more rapid accumulation of mutations in cancer genes, is believed to underlie this clinical observation. Now, researchers in the Netherlands have investigated whether nonpolypoid morphology of colorectal neoplasms might be another factor associated with the increased risk for colorectal cancer in patients with Lynch syndrome.

In a prospective study, endoscopists were given training to ensure familiarity with the classification of polypoid versus nonpolypoid colorectal neoplasms. Among 59 patients with Lynch syndrome undergoing colonoscopy, and 590 matched control patients, conventional adenomas we…