[A Case of Complete Response to Chemotherapy and Radical Resection of Unresectable Advanced Gastric Cancer].

The patient was a 75-year-old woman who was referred to our department because she had type 3 advanced gastric cancer on the posterior wall of the gastric body. Following a thorough examination, she was diagnosed as cT4aN3M1 (#16a1 int, #16b2 lat), cStage Ⅳ, an unresectable advanced gastric cancer with multiple extranodal lymph node metastases. As radical resection was not possible, chemotherapy(SOX therapy)was started. After the start of chemotherapy, the main lesion and metastatic lymph nodes shrank markedly. At the time of 7 courses, it was judged that R0 resection by conversion surgery was possible, and surgical treatment was performed. The patient underwent sub-total gastrectomy with D2 dissection and para-aortic lymph node dissection. The specimen was submitted for pathological examination and showed no residual tumor component including the main lesion and dissected lymph nodes, indicating a complete pathological response. She was started on S-1 as adjuvant chemotherapy on postoperative day 51 and has been recurrence-free for approximately 5 months after surgery.