[Experimental and clinical study of interactions between fluorinated pyrimidine derivatives and anticoagulants]

Interactions between fluorinated Pyrimidine derivatives and anticoagulants were studied experimentally and clinically, using transplanted tumor tissues of Donryu rats and tissues from lung cancer patients. In rats, which were given 5-FU, uracil, tegafur and UFT respectively, the higher tumor concentrations of 5-FU and uracil were observed when given warfarin and ticlopidine beforehand, on the other hand, the concentrations of tegafur were almost the same between rats with and without anticoagulants. In patients with lung cancer, who were given UFT and anticoagulants, the higher concentrations of 5-FU and uracil in plasma, tumor and lymph nodes were observed than those who were given UFT alone. The 5-FU concentrations in normal lung tissues were about a half of those in tumor. These results suggest a existence of the synergistic effects between fluorinated pyrimidine derivatives and anticoagulants in plasma and tissue concentrations of 5-FU.