The role of surgery after incomplete endoscopic mucosal resection for early gastric cancer

Purpose. Endoscopic mucosal resection (EMR) is a relatively new treatment option for early gastric cancer (EGC). However, cases of incomplete EMR resulting in a positive lateral margin or submucosal invasion (positive vertical margin) have been reported. We conducted this study to evaluate the role of surgery after incomplete EMR for EGC. Methods. We analyzed 19 patients who underwent gastrectomy as a result of an incomplete EMR. The patients were divided into three groups according to the type of incomplete EMR: a positive lateral margin (LM) group (n = 9), a positive vertical margin (VM) group (n = 4), and a positive lateral and vertical margin (LM + VM) group (n = 6). Results. The positive residual tumor rate and the positive lymph node rate were 44.4% (4/9) and 0% (0/9) in the LM group, 50.0% (2/4) and 25.0% (1/4) in the VM group, and 83.3% (5/6) and 16.7% (1/6), LM + VM group, respectively. Curative resection was performed in all patients and there was no recurrence in 30.8 months of follow-up. Conclusion. Radical surgery is recommended for patients with a positive lateral resection margin or submucosal invasion, or both, after EMR for EGC, because of the possibility of residual tumor or lymph node metastasis.