An unusual cause of protruding submucosal lesion in the colon (with video)

A 45-year-old man who had undergone a sigmoidectomy for sigmoid colon adenocarcinoma 3 years earlier presented with subumbilical discomfort. Abdominopelvic CT demonstrated a nodular hyperdense shadow in a protruding structure in the anastomotic area (A). Colonoscopy revealed a protruding lesion with a smooth surface and a cranial opening beside the anastomosis (B). EUS showed that the protruding lesion originated from the submucosal layer and had a mixed-echo pattern inside (C), and fecal matter kept coming out of the opening of the lesion when we infused water into the colon (Video 1, available online at www.giejournal.org).