Socioeconomic disparities in survival after high-risk neuroblastoma treatment with modern therapy

Abstract

Background: Modern therapeutic advances in high-risk neuroblastoma have improved overall survival (OS), but it is unclear whether these survival gains have been equitable. This study examined the relationship between socioeconomic status (SES) and overall survival (OS) in children with high-risk neuroblastoma and whether SES-associated disparities have changed over time.

Procedure: In this population-based cohort study, children <18 years diagnosed with high-risk neuroblastoma (diagnosis at age ≥12 months with metastatic disease) from 1991 to 2015 were identified through the National Cancer Institute's Surveillance, Epidemiology, and End Results database. Associations of county-level SES variables and OS were tested with univariate Cox proportional hazards regression. For a subcohort diagnosed after 2007, insurance status was examined as an individual-level SES variable. Multivariable regression analyses with treatment era and interaction terms were performed when SES variables reached near-significance (p ≤ .1) in univariate and bivariate modeling with treatment era.

Results: Among 1217 children, 2-year OS improved from 53.0 ± 3.4% in 1991-1998 to 76.9 ± 2.9% in 2011-2015 (p < .001). In univariate analyses, children in high-poverty counties (hazard ratio [HR] = 1.74, 95% confidence interval [CI] = 1.17-2.60, p = .007), and those with Medicaid (HR = 1.40, 95% CI = 1.05-1.86, p = .02) experienced an increased hazard of death. No interactions between treatment era and SES variables were statistically significant in multivariable analyses, indicating that differences in the OS between SES groups did not change over time.

Conclusions: Survival disparities among children with high-risk neuroblastoma have not widened over time, suggesting equitable access to and benefit from therapeutic advances. However, children of low SES experience persistently inferior survival. Interventions to narrow this disparity are paramount.

Keywords: health care disparities; health services research; insurance; neuroblastoma; pediatric oncology; poverty.

Figure 1.

Study Cohort

Figure 2.

Kaplan Meier curves of Overall Survival (A. Overall Cohort (N=1217); B. Stratified by High- and Low-Poverty County (N=1217); C. Stratified by Insurance (post-2007 Sub-Cohort, N=550); D. Stratified by treatment era)

Figure 3.

Hazard ratio plot with 95% CI of (A) Spanish/Hispanic/Latino and (B) High-poverty county in multivariate analyses controlling for treatment era and SES*treatment era interaction on overall survival. CI, confidence interval