Fluorinated pyrimidines have long been used as radiosensitizers in combined
-modality therapy for solid tumors. Nonetheless, the most commonly used dru
g, 5-fluorouracil (5-FU), is inconvenient to administer, particularly when
given by continuous intravenous infusion, Continuous infusion 5-FU does off
er a survival advantage over bolus in the treatment of lar ge bowel tumors.
This holds true regardless of whether radiation therapy is concomitantly g
iven. UFT, a combination of uracil and tegafur tin a molar ratio of 4:1), i
s an attractive alternative. Trials to date suggest at least chemotherapeut
ic equivalence compared to 5-fluorouracil, and UFT is much simpler to admin
ister. UFT is administered orally and can safely be combined with oral leuc
ovorin, 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.