Cisplatin, raltitrexed, levofolinic acid and 5-fluorouracil in locally advanced or metastatic squamous cell carcinoma of the head and neck: a phase II randomized study.

Background: Cisplatin (CDDP) is among the most active single agents against squamous cell carcinoma of the head and neck (SCCHN), and it is still the reference drug in the induction chemotherapy setting, when used in combination with infusional 5-fluorouracil (5-FU). Raltitrexed has been shown to be devoid of clinical activity against SCCHN when used alone; however, both preclinical and early clinical data regarding the combination raltitrexed-CDDP hold promise. Thymidylate synthase is the target enzyme of both raltitrexed and 5-FU; however, the two drugs have distinct sites of action on the enzyme and the combination of the two agents may be synergistic.