Measuring disparities in event-free survival among children with acute lymphoblastic leukemia in an academic institute in Oklahoma, 2005-2019

Abstract

Background: Acute lymphoblastic leukemia (ALL) is the most common type of childhood cancer. While there have been successes in the treatment of leukemia, less information is available on reasons for disparities in event-free survival (EFS) among underserved populations.

Methods: We partnered with a children's hospital at an academic institution to abstract data from the institution's cancer registry, the state cancer registry, and electronic medical records on cancer diagnosis, treatment, and outcomes for children with ALL (n = 275) diagnosed from 2005 to 2019 prior to age 20. We evaluated the relation between 1) race/ethnicity, 2) distance to the children's hospital, and 3) area deprivation with EFS, defined as time from diagnosis to relapse, death, or the end of the study period. We evaluated differences in EFS using Kaplan-Meier analysis with the log-rank test. We used the Cox Proportional Hazards Model for multivariable survival analyses.

Results: Most children were diagnosed with ALL under five years of age (45%) and with Pre-B ALL (87%). Twelve percent of children experienced a relapse and 5% died during induction or remission. EFS at 5 years was 82%. Non-Hispanic (NH) Black children had worse, though imprecise, EFS compared to NH White children (Adjusted Hazard Ratio: 2.07, 95% CI: 0.80, 5.38). Children residing in areas with higher deprivation had a higher adjusted hazard of poor outcomes compared to the least deprived areas, though estimates were imprecise (2nd quartile HR: 1.51, 3rd quartile: 1.85, 4th quartile: 1.62). We observed no association between distance to the children's hospital and EFS.

Conclusion: We observed poorer EFS for NH Black children and children residing in areas with high deprivation, though the estimates were not statistically significant. Our next steps include further evaluating socioeconomic factors in both rural and urban children to identify disparities in outcomes for children with ALL and other childhood cancers.

Keywords: Disparities; Ethnicity; Pediatrics; Precursor Cell Lymphoblastic Leukemia-Lymphoma; Racial Groups; Survival.