An extra 1-cm margin during endoscopic submucosal dissection can control subsquamous tumor extension of esophagogastric junction adenocarcinoma.

Abstract

Background and study aims: Subsquamous tumor extension can occur in cases with esophagogastric junction adenocarcinomas, which makes accurate identification of the proximal tumor margin difficult and leads to incomplete tumor resection during endoscopic submucosal dissection. We prospectively elucidated the efficacy of including an extra 1-cm safety margin during dissection for achieving negative lateral margins. Patients and Methods: Patients with suspected esophagogastric junction adenocarcinomas participated in this single-center prospective feasibility study. Oral-side markings were placed 1 cm away from the endoscopic sign or 1 cm away from the squamous-columnar junction. The primary outcome was the complete resection rate. The secondary outcomes were the treatment outcomes and the incidence, length, and diagnostic rate of subsquamous tumor extension. Results: Twelve patients were assessed. The complete resection rate was 91.7% (11/12). All lesions were contained within the 1-cm safety margin. The incidence, median length, and diagnostic rate of subsquamous tumor extension was 75%, 5.7 mm (range: 1–24.8 mm), and 66.7%, respectively. Conclusions: An extra 1-cm safety margin is safe and helpful for achieving complete negative lateral margins during endoscopic submucosal dissection for esophagogastric junction adenocarcinomas. This margin is recommended to avoid residual cancers.