[A case of advanced gastric cancer with tumor embolus in the portal vein and liver metastasis responding to S-1 plus cisplatin chemotherapy].

A 67-year-old woman presented with anemia. Computed tomography and upper gastrointestinal endoscopy revealed a primary gastric cancer with tumor embolus in the portal vein, liver metastasis, lymph node metastasis, and pancreatic involvement. Because curative surgery was deemed impossible, we started chemotherapy using S-1 (120 mg/m(2)/day for 3 weeks, followed by discontinuation for 2 weeks) plus cisplatin (80 mg/m(2)/day on days 1 and 8). After 4 courses of chemotherapy, the tumor embolus in the portal vein, liver metastasis, lymph node metastasis, and pancreatic involvement had resolved. Therefore, we performed distal gastrectomy. Histological examination revealed ypT1a, ly0, v0, ypN0 (0/49), ypCY0, ypStage IA, with a two-grade histological change in the main tumor after chemotherapy. Postoperatively, she underwent adjuvant chemotherapy with S-1 for 1 year (120 mg/m(2)/day for 4 weeks, followed by discontinuation for 2 weeks). At the 30-month follow-up after the adjuvant chemotherapy, she had no recurrence.