For patients with advanced, unresectable head and neck (HN) cancer, surgery and/or radiotherapy are the standard treatments but have poor results. A phase II trial of a continuous infusion of cisplatin, 5-FU, and high dose folinic acid (PFL) as induction chemotherapy in patients with previously untreated, locally advanced HN cancer was performed in an attempt to confirm the encouraging results reported by Dana Farber investigators using an identical regimen. Forty-five consecutive patients with unresectable HN cancer were treated every 28 days with a continuous infusion of cisplatin 25 mg/m(2)/day (days 1-5), 5-FU 800 mg/m(2)/day (days 2-6), and folinic acid 500 mg/m(2)/day (days 1-6). After three courses of chemotherapy, patients were treated with surgery and/or radiotherapy. Objective responses were observed in 26 of 38(69%) evaluable patients with 14(37%) clinical complete responses. Grade III-IV toxicity was important and consisted mainly of mucositis and neutropenia that were found in 47 and 18%, respectively , of patients after the first course. There was one toxic death. PFL is an active, toxic induction regimen for far-advanced HN cancer, yielding a response rate in the range of the widely used cisplatin and 5-FU (PF) schedule; a comparative trial is warranted before concluding that PFL is superior to the latter combination.