Dr Sumit Gupta (University of Toronto, Canada) and colleagues investigated 24,979 patients with ALL, ranging from 0–31 years of age, who were enrolled in COG frontline ALL trials between 2004 and 2019, to study health outcomes across race, ethnicity, SES, and disease prognosticators. SES was inferred by insurance status.
The main outcomes were event-free survival (EFS) and overall survival (OS). Change in estimate approach was used to evaluate the relative contribution of race/ethnicity, SES, and disease prognosticators. The 5-year EFS rates among White (87.4%) and Asian patients (88.1%) was higher than the 5-year EFS rates among Hispanic (82.8%) and Black patients (81.9%).
Furthermore, the EFS rate was higher in patients with a non-US insurance (89.0%), or a private insurance (86.3%) compared with patients who received federal support for healthcare costs via US Medicaid (83.2%). In addition, change in estimate analysis revealed that the reported disparities could not be fully explained by disease prognosticators or leukaemia biology.
In Hispanic patients, the hazard ratio for EFS changed from 1.37 to 1.11 when adjusting for SES and disease prognosticators, demonstrating a significant influence of these factors. In Black patients, the hazard ratio changed from 1.45 to 1.32 after adjustment, leaving a significant proportion of the increased risk in this subgroup unexplained by adjustment. Dr Gupta added that the observed disparities in OS were wider, indicating that access to relapse care may be insufficient in various subgroups.
Notably, additional analysis showed that the results were significant in patients with B-lineage disease phenotype (P<0.001), but not in patients with T-lineage disease phenotype (P=0.47). Dr Gupta argued that future studies should investigate access to care, quality of care, and institutional racism to explain the reported disparities.
1. Gupta S, et al. Racial, Ethnic, and Socioeconomic Factors Result in Disparities in Outcome Among Children with Acute Lymphoblastic Leukemia Not Fully Attenuated By Disease Prognosticators: A Children’s Oncology Group (COG) Study. O612, ASH 2021 Scientific Sessions, 11–14 December.