[Combination chemotherapy with orally administered UFT and leucovorin (LV)]

We evaluated the efficacy of the combination therapy of UFT with Leucovorin (LV) against mouse colon adenocarcinomas and human colon adenocarcinoma. In vitro studies, it was shown that LV potentiated the cytotoxicity of FUra against 7 out of 9 cell lines used in this experiment. In vivo studies, the antitumor activity of UFT against mice bearing colon 38 adenocarcinoma was increased following administration of LV either before, after or at the time of treatment with UFT. Further studies were performed on the combination effect of UFT and LV against mouse colon 26 adenocarcinoma and human colon adenocarcinoma KM20C. Consequently, the combined treatment of UFT with LV was more effective than UFT alone against two cell lines. Our studies suggest that combination chemotherapy of UFT with LV is a promising approach for the treatment of a human colon cancer in clinical practice.