Results of therapy for acute lymphoblastic leukemia in black and white children

Context Treatment results for acute lymphoblastic leukemia (ALL) clearly have improved over the past decade, but black children have not fared as well as white children in large national trials. Objective To compare the clinical outcomes of therapy for black and white children with ALL treated at a single institution. Design, Setting, and Patients A retrospective analysis of 412 children and adolescents (68 black, 338 white, and 6 other race) with newly diagnosed ALL who were treated consecutively at a pediatric cancer center in Memphis, Tenn. Patients were enrolled from December 1991 to July 1998 in successive Total Therapy studies regardless of race, ethnicity, or ability to pay and received risk-directed therapy according to stringent criteria. Interventions All patients received the same intensive, remission-induction therapy followed by 120 weeks of risk-assigned postremission therapy that included reinduction treatment, pulses of high-dose methotrexate, and early intensification of intrathecal chemotherapy. Main Outcome Measures Event-free and overall survival rates for black and white children were estimated by the method of Kaplan and Meier and compared with the Mantel-Haenszel test and by Cox proportional hazards regression analysis, adjusting for known prognostic factors. Results The 68 black children were significantly more likely than the 338 white children to have higher-risk prognostic features, including an initial leukocyte count greater than 100 X 10(3)/muL, a T-cell immunophenotype, and the t(1;19) chromosomal translocation with E2A-PBX1 fusion, and were less likely to have hyperdiploid blast cells, a favorable prognostic factor in childhood ALL. However, the clinical outcomes for these 2 cohorts were not significantly different: 5-year event-free and overall survival rates were 80.7% (95% confidence interval [CI], 70.3%-91.1%) and 86.2% (95% Cl, 77.2%-95.2%) for black children vs 79.4% (95% CI, 74.7%-84.1%) and 85.0% (95% Cl, 80.9%-89.1%) for white children. Ten-year results also were comparable, but the Cls were wide because of the small numbers of patients who had been followed up for 10 years or more. The lack of a racial effect on the long-term outcome of therapy was still apparent in a multivariate Cox regression analysis, adjusting for sex, age, presenting leukocyte count, leukemic cell DNA index, immunophenotype, and central nervous system status. Conclusion With equal access to effective antileukemic therapy, black and white children with ALL can expect the same high rate of cure.