[CR of rectal cancer and synchronous liver and lung metastases obtained with TS-1 plus CPT-11 combination therapy--case report].

: The patient was a 44-year-old male in whom low anterior resection of the rectum, partial pneumonectomy, and liver biopsy were performed because of suspicion of synchronous liver and pulmonary metastases of rectal cancer which caused familial adenomatous polyposis. Because anticancer drug sensitivity testing by the HDRA method performed on tissue collected from the cancer immediately postoperatively revealed sensitivity to 5-FU and CPT-11, and measurement of nucleic acid metabolizing enzymes showed a high level of DPD, a 5-FU metabolizing enzyme, combination therapy with TS-1 and CPT-11 was started. TS-1, 120 mg/body, was administered on 14 consecutive days followed by a 7-day rest period, and CPT-11, 120 mg/body, was administered on day 1 and day 8. One cycle was defined as 3 weeks,and cycles were repeated. Grade 2 diarrhea occurred, but the CPT-11 dose was reduced to 100 mg/body, and treatment was continued. CR was achieved when the 4th course had been completed. Thoracic and abdominal CT was performed after 4 courses, but no recurrent foci were detected in the residual lung tissue, and all of the metastatic liver foci had resolved. To date 6 courses have been completed, and no relapses have been detected by thoracic CT. We report a case in which it was possible to predict efficacy as a result of treatment based on anticancer drug sensitivity testing and measurements of nucleic acid metabolizing enzymes.