Small cell carcinoma of the lung experience with a six‐drug regimen

Thirty‐seven patients with small cell carcinoma of the lung and no prior chemotherapy were treated with a program involving the alternation of two three‐drug regimens, each composed of individually active agents with different mechanisms of action. The two treatment phases consisted of: 1) cyclophosphamide, 1000 mg/m2; adriamycin, 30 mg/m2; and vincristine, 1.4 mg/m2, all given intravenously (IV) on days 1 and 22 (CAV); and 2) 1,3‐bis(2‐chlorethyl)‐1 nitroso‐urea (BCNU), 100 mg/m2 IV on days 43 and 44; methotrexate, 30 mg/m2 IV on days 50 and 64; and procarbazine, 100 mg/m2 orally from days 51 through day 64 (BMP). Treatments were recycled with CAV on day 85. Radiation therapy was used to control local disease that did not respond completely to chemotherapy, as well as to palliate local symptoms from progressive cancer. Of the 31 patients evaluable for a response to chemotherapy and radiation therapy, 71% demonstrated complete or partial (>50%) tumor regression, with a median response duration of seven months (range = 1–25+ months). The median survival time from start of therapy was 11.5 months for patients with limited disease and 7.5 months for those with extensive disease. Toxicity included universal nausea and vomiting; leukopenia (leukocyte count <3000/μl) in 29% during CAV and 27% during BMP with two episodes of injection and one death; and thrombocytopenia (platelets <50,000/μl in 3% during CAV and 42% during BMP. The present six‐drug program has thus failed to demonstrate any obvious advantage over our previous four‐drug regimen10.