[Evaluation of combination chemotherapy with 5-FU and CDDP for human gastric carcinoma transplanted into nude mice].

Combined chemotherapy of 5-FU and CDDP is useful for advanced or recurrent gastric cancer. To evaluate the efficacy of this chemotherapy, using human gastric carcinoma (NSC-30) maintained in the subcutaneous (sc) space in nude mice, we designed the following four experimental groups: 1) control group, 2) 5-FU group, 3) CDDP group, and 4) combined therapy group of 5-FU and CDDP (FP group). 5-FU (150 mg/kg) was injected into the intraperitoneal space for seven days using AlZet osmotic pumps. CDDP (9 mg/kg) was injected into the intraperitoneal space at one time. The tumor growth of drug administered groups was inhibited compared with the control group, especially in the FP group. Body weight and general condition of nude mice did not differ between groups. We also measured tumor concentrations of 5-FU and thymidylate synthetase (TS) total, free, inhibition rate between 5-FU group and FP group. The tumor 5-FU concentration of FP group was slightly higher than in 5-FU group, but the TS inhibition rate was almost the same. In conclusion, this combined therapy using Alzet osmotic pump is a useful drug sensitivity test as a conventional system.