[Pilot phase II study of 5-day continuous infusion of cisplatin in treatment of non-small cell lung cancer].

We administered cisplatin (CDDP) as a single agent at a dose of 25 mg/m2/day for 5 days by continuous infusion in 15 patients with inoperable non-small cell lung cancer (3 squamous cell carcinoma, 11 adenocarcinoma and 1 large cell carcinoma), and studied the pharmacokinetics of CDDP, the response rate and toxic effects. The maximum concentration (Cmax) of filtrable platinum (Pt) was 0.092 +/- 0.03 microgram/ml and AUC was 9.3 +/- 3.5 micrograms.hr/ml. The response rate was 40% (6/15). Nausea without vomiting was noticed in 53% of patients and vomiting in 27%. Leukopenia (less than 3,000/mm3) was seen in 53%, thrombocytopenia (less than 70,000/mm3) in 27% and anemia (Hb less than 9.5 g/dl) in 67%. Peak serum creatinine greater than 1.5 mg/dl was not observed. The Cmax of the filtrable Pt was low but AUC level was high compared with that in reported data in which CDDP as a single agent was infused at the same dose in short-term infusion. This was presumably associated with the good response rate in this study. The incidence of hematologic toxicity was slightly high, while that of vomiting and nephrotoxicity was rather low. The 5-day continuous infusion appears to be a safe and effective method of CDDP administration for non-small cell lung cancer, and improved therapeutic results may be expected when this is combined with other effective drugs.