Time trends in survival in acute lymphocytic leukemia.

Comparison of patients under 20 years of age with acute lymphocytic leukemia diagnosed in 1955-64 with those whose disease was diagnosed in 1965-69 revealed a marked improvement in median survival time, from 9.5 to 16.8 months. This improvement occurred among patients with less favorable hematologic and symptomatic characteristics as well as among patients with more favorable ones. However, a shift in patient characteristics was consistent with the concept of diagnosis earlier in the natural history of the disease. In the more recent period, fewer patients were classified as severely disabled, and a somewhat higher proportion were in more favorable categories with respect to platelet count, percent of polymorphonuclear leukocytes, organomegaly, and bleeding or infection. Initial treatment was markedly different during the two time periods; this reflected a shift toward the use of combinations of chemotherapeutic agents and steroids.