a substance being studied in the treatment of some types of cancer. it is a combination of tegafur and uracil. the tegafur is taken up by the cancer cells and breaks down into 5-fu, a substance that kills tumor cells. the uracil causes higher amounts of 5-fu to stay inside the cells and kill them. ftorafur is a type of antimetabolite. also called tegafur-uracil, uft, and uftoral.