The role of additional chemotherapy with oral UFT in intravenous combination chemotherapy with cisplatin and 5-fluorouracil for human gastric cancer xenograft lines of well- and poorly- differentiated adenocarcinomas transplanted in nude mice.

In order to assess the role of maintenance chemotherapy with the oral anticancer agent UFT, a mixture of uracil and futraful, in the intensive intravenous chemotherapy for gastric cancer, nude mice transplanted with human gastric cancer xenografts were treated with intravenous 5-fluorouracil (5-FU) and cisplatin (CDDP), alone or in combination, with or without the oral anticancer agent UFT. UFT was given at its maximal clinical dose of 10 mg/kg of body weight daily for 2 weeks, while 5-FU and/or CDDP was intravenously administered at the dose of 20 mg/kg and 1.8 mg/kg of body weight respectively once a week, alone or in combination, for two weeks. The results revealed that 5-FU or CDDP alone were ineffective for both GC-YN, a well differentiated adenocarcinoma line, and GC-SF, a poorly differentiated adenocarcinoma line; however, UFT was effective for GC-SF. In combinations, only the three-agent combination 5-FU + CDDP + UFT (FPU) was effective for GC-YN; however, all the two-agent combinations and FPU were effective for GC-SF. FPU significantly suppressed the growth of GC-YN much more than all the other treatment groups. In contrast, although all combinations as well as UFT alone were effective for GC-SF, there was no significant difference among these effective groups. Moreover, no side effects were noted in combined use of UFT. This study suggests that oral UFT as a maintenance treatment may be beneficial in the combination chemotherapy for human gastric cancer.