Lymph node metastasis after endoscopic submucosal dissection of a differentiated gastric cancer confined to the mucosa with an ulcer smaller than 30 mm.

In the expanded indications for endoscopic resection, Japanese guidelines for gastric cancer include differentiated cancers confined to the mucosa with an ulcer <30 mm. We describe a patient with lymph node metastasis after curative endoscopic submucosal dissection (ESD) for a tumor of this indication. The patient was a 70-year-old man with chronic hepatitis C. He underwent ESD for early gastric cancer in May 2010. Pathology revealed a moderately differentiated adenocarcinoma, 22 × 17 mm in size, that was confined to the mucosa with an ulcer. The horizontal and vertical margins were negative for the tumor. We diagnosed thiscase as curative resection of expanded indication and followed this patient with endoscopy, abdominal ultrasonography (AUS) or enhanced computed tomography (CT) approximately every 6 months. After 17 months, lymph node metastasis was detected with AUS and CT and diagnosed by endoscopic ultrasound-guided fine-needle aspiration biopsy in August 2011. Distal gastrectomy with D2 dissection was carried out in December 2011. Although it is low, the possibility of recurrence should be borne in mind after endoscopic treatment of early gastric cancer, despite its inclusion in the expanded indications for endoscopic resection.