Predictors of Cancer in Large Rectal Polyps That Appear Benign

In a post hoc analysis of large (≥3 cm) nonpedunculated rectal polyps that were randomized to removal via endoscopic mucosal resection (EMR) or transanal endoscopic microsurgery, researchers evaluated predictors of incidental finding of invasive rectal cancer.

Rectal cancer that was unexpected occurred in 13% of patients. For the EMR procedures, compared with benign adenomas, unexpected cancers had a lower rate of successful submucosal lifting (60% vs. 93%), and their resections were more often considered incomplete (33% vs. 10%) and were more frequently terminated prematurely (60% vs. 8%).