Additional surgical resection after endoscopic mucosal dissection for early gastric cancer: A medium-sized hospital's experience

In Japan, the majority of early gastric cancers (EGCs) are now treated with endoscopic submucosal dissection (ESD). Patients with non-curative lesions treated by ESD are advised to undergo additional surgical resection (ASR) based on guidelines from the Japan Gastroenterological Endoscopy Society (JGES) and Japanese Gastric Cancer Association (JGCA). However, many studies have demonstrated that residual cancer and lymph node metastasis are only rarely found in ASR specimens. Here we retrospectively analyzed the conditions that could enable the avoidance of unnecessary ASR.The ESD data for 114 absolute indication lesions and 26 lesions of expanded indication lesions were analyzed. The indications and the curability were evaluated according to the JGES/JGCA guidelines.The rates of non-curative resection and ASR were significantly higher in the expanded indication group compared to the absolute indication group (26.9% and 19.2% vs. 7.9% and 0.9%, respectively). ASR was performed for six patients. Three of their ARS specimens contained neither residual cancer nor lymph node metastasis, and the pathological findings of the preceding ESD specimens deviated slightly from the curative criteria defined by the guidelines. The conditions of the lesions that did not meet the curative criteria were as follows: (1) sm1 invasion of undifferentiated-type lesion <10 mm dia., (2) 21-25 mm dia. mucosal undifferentiated-type lesion, or (3) peacemeal resection with a horizontal margin positive for the mucosal differentiated-type.These data suggest that a close follow-up without ASR might be appropriate for patients in the above-mentioned three categories after non-curative ESD for EGC.