The role of UFT in combined-modality therapy.

Fluorinated pyrimidines have long been used as radiosensitizers in combined-modality therapy for solid tumors. Nonetheless, the most commonly used drug, 5-fluorouracil (5-FU), is inconvenient to administer, particularly when given by continuous intravenous infusion. Continuous infusion 5-FU does offer a survival advantage over bolus in the treatment of large bowel tumors. This holds true regardless of whether radiation therapy is concomitantly given. UFT, a combination of uracil and tegafur (in a molar ratio of 4:1), is an attractive alternative. Trials to date suggest at least chemotherapeutic equivalence compared to 5-fluorouracil, and UFT is much simpler to administer. UFT is administered orally and can safely be combined with oral leucovorin. There is profound scientific rationale for using UFT with radiation therapy, and early trials in gastrointestinal malignancies demonstrate the safety and efficacy of the combination. Further studies will determine the optimal timing and uses for concomitant UFT and radiation therapy.