[A Case of Advanced Gastric Cancer with a Pathological Complete Response after Neoadjuvant Chemotherapy(S-1/Oxaliplatin)].

A 63-year-old man was seen by his family doctor for epigastric distress, and he was referred to our hospital with a diagnosis of gastric cancer. Upper gastrointestinal endoscopy revealed type 3 gastric cancer(por1>tub2>tub1)at the lesser curvature of the stomach. Computed tomography suggested thickening of the wall of the stomach at the lesser curvature and bulky lymph node swelling. After a diagnosis of cT4a cN2M0, cStage III B advanced gastric cancer, we treated him with neoadjuvant chemotherapy consisting of 3 courses of SOX(oxaliplatin 100mg/m / 2 on day 1, S-1 120mg/day on day 1-14, followed by 7 days of rest). After the chemotherapy, because the primary tumor and lymph nodes were reduced, we performed distal gastrectomy with D2 lymph node dissection. Histopathological examination revealed no residual cancer cells, indicating a pathological complete response(Grade 3). We report a case of advanced gastric cancer with a pathological complete response after neoadjuvant chemotherapy.