Precision medicine and health disparities: The case of pediatric acute lymphoblastic leukemia

Abstract

Background: Precision medicine has uncertain potential to address population health disparities.

Purpose: Case study of disparities in pediatric acute lymphoblastic leukemia (ALL).

Method: Literature-based evaluation of ALL in African American (AA) and European American (EA) children.

Findings: AA children have a lower incidence of ALL than EA children, experience higher relapse rates, and are more likely to be diagnosed with poor prognostic indicators. Environmental risk exposures for ALL have small effect sizes; data are insufficient to determine their contribution to differences in incidence and prognosis. Differences in prevalence of gene variants associated with treatment response contribute to higher relapse rates in AA children. However, higher relapse rates were not seen in a care setting that eliminated out of pocket costs, used risk-directed therapy, and included rigorous case management.

Discussion: Unequal access to effective treatment contributes to ALL disparities. Precision medicine can help to define effective treatment for diverse patient populations.

Keywords: Childhood leukemia; Health disparities; Pharmacogenomics; Precision medicine.

Figure. Cancer Health Disparities and Precision Health Research.

The ALL example illustrates the complex interplay between social determinants and genetics in cancer outcomes. Racial disparities in ALL outcomes can be largely accounted for by differences in access to effective treatment. Effective treatment in turn is informed by precision health research that includes study of inherited differences in treatment response. Further understanding of unexplained aspects of ALL in African American populations, including the lower incidence of the disease but higher rate of adverse prognostic indicators, will require both evaluation of differences in risk exposure and the contribution of epigenetics and inherited and somatic genetic variation to etiology and disease sub-types.