Abstract
Background and study aims A 71-year-old female underwent endoscopic submucosal dissection (ESD) for a subcircumferential
lateral-spreading rectal tumor. Pathological examination showed an intramucosal adenocarcinoma
in villous adenoma (size: 155 × 140 mm), which had been curatively resected with negative
margins. However, follow-up colonoscopy revealed a tumor at the ulcer scar site, which
soon grew into a circumferential lesion. Nineteen months after the first ESD procedure,
additional ESD was performed for the recurrent lesion, which was resected en bloc
without any adverse events, although severe fibrosis was noted in the submucosa. Pathological
examination revealed a villous adenoma similar to the primary lesion with negative
margins, but tumor cell nests were also present in the submucosa, which implied that
tumor cell implantation had occurred during the first ESD. The post-ESD ulcer bed
was subjected to argon plasma coagulation to prevent tumor recurrence after confirmation
of the pathological results. There have not been any signs of recurrence during 9
years of follow-up.
