[Highly Advanced Gastric Cancer Leading to Immediate Perforation on Day Three of Chemotherapy with S-1 plus Oxaliplatin].

: A 68-year-old woman was diagnosed with advanced gastric cancer with a type 3 deep ulcer of the middle stomach by endoscopy. An abdominal computed tomography scan revealed multiple lymph node metastases and peritoneal disseminations. The clinical stage was determined to be T4a(SE), N2P1M1(PER), H0 and stage IV . A gastrectomy was scheduled after 2 courses of S-1 plus oxaliplatin(SOX)with curative intent. On day 3 after initiatingSOX therapy, the patient complained of severe abdominal pain. Because the abdominal CT scan showed intra-abdominal free air and a defect in the gastric wall, we performed an emergency total gastrectomy. The defect in the gastric wall was about 1 cm in diameter and was located in the anterior wall of the lower body, consistent with the center of the tumor. The operative findings suggested that the perforation was caused by chemotherapy-induced necrosis of gastric cancer cells. The patient was discharged 16 days after surgery and received post-operative chemotherapy. Our findings suggest that the risk of gastric perforation should be considered when administeringchemotherapy to patients with advanced gastric cancer and a deep ulcer.