Combination chemotherapy for terminal-phase chronic granulocytic leukemia: cancer and leukemia group B studies.

A 34% response was obtained in 202 evaluable patients in the terminal phase of chronic granulocytic leukemia using combinations of hydroxyurea, 6-mercaptopurine, and corticosteroids. Twelve percent of responses were complete and 22% partial. Overall median survival was 12 wk. A 30 wk median survival for responding patients was statistically superior to the 7-wk survival for nonresponders (p less than 0.001). Response was inversely correlated with toxicity. No responses were obtained in patients sustaining both severe infectious and bleeding complications. No benefit could be demonstrated from the addition of vincristine in induction and daunorubicin for consolidation. Although the response frequency and duration of survival with this combination chemotherapy were generally superior to those previously reported by our group, the terminal phase of chronic granulocytic leukemia still remains a formidable and generally refractory disease.