Effect of horizontal margin status and risk of local recurrence after endoscopic submucosal dissection for superficial esophageal cancer.

Background And Aim: Endoscopic submucosal dissection (ESD) sometimes results in bloc resection with a positive or inconclusive horizontal margin (HM1 or HMX, respectively) on histological evaluation. The specific risk for such situations is unclear. We therefore investigated the outcome of ESD with HM1 or HMX.