Eighty-two patients with advanced or recurrent squamous cell carcinoma of the head and neck were treated with bolus cisplatin and 120-h infusion of 5-fluorouracil. Among 49 pretreated patients, there were 9 complete and 12 partial responses, for an overall response rate of 43% and a median estimated survival of 8 months. Hematologic toxicity in this group was relevant, with 4 early deaths and 30% of cases with moderate to severe leukopenia; mucosal and renal toxicities were also important. Among 33 patients with no prior therapy, there were 8 complete and 17 partial responses, for an overall response rate of 76%. Fifteen of the 25 responding patients received subsequent locoregional treatment. The median estimated survival in this group was 29 months. Hematologic, mucosal, and renal toxicities were only mild to moderate. Episodes of possible 5-fluorouracil-related cardiotoxicity were recorded in both pretreated and untreated patients. Twelve of 41 partial responses observed after the second cycle of therapy were converted to complete responses with a third (8 cases) and also a fourth (4 cases) course. This study confirmed that cisplatin plus 5-fluorouracil is a first-choice combination in previously untreated patients. Definitive evidence that chemotherapy can favorable influence survival awaits confirmation by randomized trials, using a control arm with conventional locoregional treatment. In previously treated patients with recurrent disease, less intensive regimens not requiring hospitalization seem more useful for the quality of life.