Antitumor activity of UFT and docetaxel on human breast carcinoma xenografts

: The effect of fluorinated pyrimidine co-administered with docetaxel on transplantable human breast cancer strains MX-1 and R-27 was investigated using an in vitro succinic dehydrogenase inhibition (SDI) method and an in vivo nude mouse transplant method. The in vivo results showed that the combined use of 5-fluorouracil and docetaxel enhanced antitumor activity. No antitumor activity on MX-1 was observed in vivo in either the UFT alone or docetaxel alone group, whereas co-administration of the two drugs resulted in a tumor inhibition rate of 85.1% above the effective line. These results suggest the usefulness of 5-fluorouracil in combination with docetaxel in the treatment of solid tumors.