Cyclophosphamide and CCNU in the treatment of inoperable small cell carcinoma and adenocarcinoma of the lung

Abstract

Two hundred and fifty-eight patients with small cell carcinoma and 185 patients with adenocarcinoma were centrally randomized to receive either cyclophosphamide (1000 mg/m2 every 3 weeks) iv or cyclophosphamide (700 mg/m2 every 3 weeks) iv plus CCNU (70 mg/m2 every 6 weeks) orally. Those patients who were initially treated with the single agent were then treated with CCNU (130 mg/m2 every 6 weeks) at the time of cyclophosphamide failure. Objective tumor regression occurred more frequently with the combination regimen in patients with small cell carcinoma (43% vs 22%, P = 0.002), but no difference in response rates was apparent in patients with adenocarcinoma. In both cell types patients survived somewhat longer following treatment with the combination. The overall incidence of severe toxicity was equal for the two regimens in both cell types; however, the therapeutic index of the combination was superior to that of the single agent in small cell carcinoma. Severe drug toxicity was more frequent in small cell carcinoma patients with extensive disease, and survival was reduced in both cell types with extensive disease. Survival was better for ambulatory patients in both cell types and women survived longer than men. In women with small cell carcinoma, ambulatory status also was associated with a higher incidence of tumor regression. In patients with small cell carcinoma those who had prior lung surgery survived longer than those without prior surgery. Previous radiation therapy was associated with a reduced incidence of objective regression in men with small cell carcinoma. In both cell types patients with tumor regression lived longer than nonresponders; however, objective disease stability was associated with improved survival only in patients with adenocarcinoma. Stratification in future studies should consider extent of disease, performance status, sex, and prior therapy.