Background: Cisplatin, 5-fluorouracil, and leucovorin (PFL) have demonstrated synergistic activity in preclinical models. Continuous infusion of these agents maximizes the potential for synergistic interaction and forms the basis of the PFL regimen.
Methods: Sixty-one patients with advanced (Stages IIIB and IV) non-small cell lung cancer were entered into the study. Thirty-one were treated with cisplatin 25 mg/m2/day on days 1-5, 5-fluorouracil 800 mg/m2/day on days 2-6, and calcium leucovorin 500 mg/m2/day on days 1-6. Because of severe mucositis, the final 30 patients were treated with the same dosage of cisplatin but with the deletion on day 6 of leucovorin and 5-fluorouracil. Cycles were repeated every 28 days. Response was assessed after two cycles. Responding patients received an additional two cycles. Patients with Stage IIIB disease received radiation therapy to the mediastinum and sites of involved disease.
Results: PFL had an overall response rate of 41%. Median survival was 8.1 months, and median time to treatment failure was 4.2 months. Importantly, 68% (17 of 25) of responses were maximal after just two cycles of chemotherapy. Notable toxicities included mucositis (43% > or = Grade 3) and myelosuppression. Response, time to failure, or survival did not differ between the two schedules. Mucositis was less severe with 4-day PFL.
Conclusions: PFL as given in this manner is an active regimen for the treatment of patients with advanced non-small cell lung cancer. The rapidity of response makes it a regimen for incorporation into protocols for Stage IIIA disease. A neoadjuvant study using PFL is underway.