Survival of childhood acute lymphoblastic leukemia: results of therapy at Tata Memorial Hospital, Bombay, India.

The purpose of this study was to analyze the outcome of patients who completed therapy for acute lymphoblastic leukemia (ALL) and to study the role of an aggressive induction regimen in preventing post therapy relapses. Four hundred and twenty-two patients with ALL who completed therapy during the period 1975-1991 were followed. Two hundred and sixty patients received the aggressive MCP 841 protocol and 162 patients received various other less aggressive treatment regimens. Patients were followed with periodic examination and complete blood counts. The incidence of post therapy relapse was 27% in the less aggressive protocols and 15% in the MCP 841 protocol (p = 0.001). An higher percentage of relapses was seen in males (p = 0.05) and 89% relapses occurred within two years of stopping therapy. The relapse rate after 5 years of cessation of therapy was 0.59%. In conclusion, aggressive induction therapy is the most crucial factor in predicting relapses following cessation of therapy in ALL patients. However, relapses are unlikely to occur five years post therapy.