Outcome of children treated for relapsed acute lymphoblastic leukemia in Central America

Abstract

Background: Outcomes for relapsed childhood acute lymphoblastic leukemia (ALL) have not been documented in resource-limited settings. This study examined survival after relapse for children with ALL in Central America. METHODS: A retrospective cohort study was performed and included children with first relapse of ALL in Guatemala, Honduras, or El Salvador between 1990 and 2011. Predictors of subsequent event-free survival (EFS) and overall survival (OS) were examined. RESULTS: There were 755 children identified with relapsed disease. The median time from diagnosis to relapse was 1.7 years (interquartile range, 0.8-3.1 years). Most relapses occurred during (53.9%) or following (24.9%) maintenance chemotherapy, and the majority occurred in the bone marrow (63.1%). Following the initial relapse, subsequent 3-year EFS (± standard error) and OS were 22.0% ± 1.7%, and 28.2% ± 1.9%, respectively. In multivariable analysis, worse postrelapse survival was associated with age ≥ 10 years, white blood cell count ≥ 50 × 109/L, and positive central nervous system status at the original ALL diagnosis, relapse that was not isolated central nervous system or testicular, and relapse < 36 months following diagnosis. Site and time to relapse were used to identify a favorable risk group whose 3-year EFS and OS were 50.0% ± 8.9% and 68.0% ± 8.1%, respectively. CONCLUSIONS: Prognosis after relapsed ALL in Central America is poor, but a substantial number of those with favorable risk features have prolonged survival, despite lack of access to stem cell transplantation. Stratification by risk factors can guide therapeutic decision-making. Cancer 2013. © 2012 American Cancer Society.