Outpatient weekly 24-hour infusional adjuvant chemotherapy of cisplatin, 5-fluorouracil, and leucovorin for high-risk nasopharyngeal carcinoma

Background. Distant metastasis rather than locoregional recurrence is the major site of failure after adequate radiotherapy in nasopharyngeal carcinoma (NPC). The aim of this study is to evaluate the toxicity and survival of outpatient weekly 24-hour infusion adjuvant chemotherapy for NPC patients with high-risk of distant failure. Methods. Our definition of high-risk NPC included patients with (1) 1992 AJCC staging system of N3, T4N2, or N2 with one of nodal size > 4 cm; (2) supraclavicular node metastasis; and (3) residual disease after radiotherapy or neck relapse. From August 1994 to August 1997, 41 NPC patients matching the preceding criteria agreed to receive weekly PFL (cisplatin 25 mg/m(2), 5-fluorouracil 1250 mg/m(2), and leucovorin 120 mg/m(2)) adjuvant chemotherapy for a total of 18 weeks. Clinical data of another 88 patients with similar disease status who did not receive adjuvant chemotherapy during the same period were collected and analyzed for comparison. Survival analysis was investigated by the Kaplan-Meier method and the Cox proportional hazards model. Results. A total of 700 weekly chemotherapy doses was delivered to 41 patients. The ratio of actual/planned dose delivery was 94.9%. Grade 3-4 toxicity of adjuvant chemotherapy included leucopenia (7.3%), anemia (2.4%), thrombocytopenia (2.4%), and nausea/vomiting (2.4%). After a median follow-up of 70 months, 26.8% (11 of 41) and 47.7% (42 of 88) of patients in PFL and no adjuvant chemotherapy groups had distant metastasis (p =.0247). The 5-year metastasis-free survival rates were 71.9% for the PFL group compared with 48.4% for no adjuvant chemotherapy patients (p =.0187). The 5-year overall survival rates were 53.7% (PFL group) and 38.3% (no adjuvant chemotherapy group), respectively (p =.0666). Multivariate Cox analysis showed PFL adjuvant chemotherapy was the independent factor that predicted metastasis-free survival after adjustment for other variables. Conclusions. Outpatient weekly 24-hour continuous infusion PFL adjuvant chemotherapy is a well-tolerated regimen with promising results in high-risk NPC patients and merits investigation in phase III studies. (C) 2003 Wiley Periodicals, Inc.