Full-thickness resection with an over-the-scope device: possible translocation of adenoma tissue in a case of an incomplete resection at the appendix

Background and study aims  Clip-assisted endoscopic full-thickness resection has great potential for treatment of difficult-to-resect colorectal neoplasia. Here, we report on endoscopic full-thickness resection at the appendiceal orifice with the appendix in situ requiring emergency surgery due to acute appendicitis. Final histopathology showed appendicitis and residual serrated adenoma within the appendiceal stump, but unexpectedly, also a displaced adenoma fragment at the serosal surface of the cecum. Given the transmural placement of the clip prior to snare resection, translocation of neoplastic tissue to the extra luminal site in cases of incomplete adenoma/carcinoma resection could be a concern.