[A case of gastric carcinosarcoma treated with surgical resection and irinotecan and mitomycin C combination therapy].

A 59-year-old man was admitted following episodes of melena. Upper gastrointestinal endoscopy revealed a type 2 carcinoid-like tumor in the cardium of the stomach. Histopathological analysis of a biopsy specimen revealed adenocarcinoma. Although hepatic metastases were detected, total gastrectomy was initially performed for hemorrhage control. The final histopathological diagnosis of the resected primary tumor was gastric carcinosarcoma with an osteosarcoma component. After ineffective first-line combination therapy with S-1 (tegafur, gimeracil, and oteracil) and cisplatin, irinotecan and mitomycin C chemotherapy was introduced. Although the hepatic metastases showed shrinkage after three courses of the chemotherapy, the patient succumbed seven months after surgery. This case report suggests that systemic chemotherapy using irinotecan and mitomycin C may be effective in the treatment of gastric carcinosarcoma with an osteosarcoma component and distant metastases.