[Complete response of primary tumor in a case of advanced gastric cancer with liver metastasis treated by TS-1 plus divided administration of CDDP].

A 62-year-old female patient was hospitalized for general fatigue and appetite loss. Type 3 gastric cancer (moderate differentiated adenocarcinoma) with liver metastasis (S8) and direct invasion to the retro-peritoneal space and duodenal third portion was detected by endoscopic and radiographic examination. This case was judged to be unresectable from these findings. TS-1 plus divided administration of CDDP was performed. TS-1 (100 mg/day) was administrated from day 1 to 21 followed by 14 days rest as one course. CDDP (20 mg/m2) was infused for 2 hours on day 1, 8, and 15. One course was done in the hospital, and the following 2 courses as ambulatory treatment. Grade 2 neutropenia was observed as an adverse reaction. At the completion of 3 courses, partial response in the primary tumor, complete response in the duodenal third portion and no change in the liver metastasis were assessed by examination. Because of this remarkable down-staging, distal gastrectomy and radiofrequency ablation (RFA) for liver metastasis were performed. There was no evidence of direct invasion to the other organs from the primary tumor in intraoperative findings. Pathological examination revealed the disappearance of carcinoma cell in the resected stomach and the surrounding lymphnodes. In conclusion, this chemotherapy regimen has an excellent antitumor effect with low toxicities. Therefore, this regimen was comparatively safe for outpatients and was an effective neo-adjuvant chemotherapy.