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.