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.
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.
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
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 × 103/µL, 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% CI, 77.2%-95.2%) for black children vs 79.4% (95% CI, 74.7%-84.1%)
and 85.0% (95% CI, 80.9%-89.1%) for white children. Ten-year results also
were comparable, but the CIs 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.
With equal access to effective antileukemic therapy, black and white
children with ALL can expect the same high rate of cure.