Evaluating Disparities in Pediatric Cancer Genomic Testing and Sequencing Results at the University of California, San Francisco Using the National Childhood Cancer Registry.

Abstract

PURPOSE: The increasing role of genomic testing in pediatric cancer care decisions may contribute to outcome disparities. We evaluated drivers of genomic testing in the National Childhood Cancer Registry (NCCR) at the University of California, San Francisco (UCSF). MATERIALS AND METHODS: Multilevel data linkages for 1,555 patients with cancer age ≤20 years diagnosed between 2012 and 2019 at the UCSF NCCR were leveraged for a subset of patients who were alive and diagnosed after 2015 following the availability of UCSF500 genomic testing, a panel-based, next-generation cancer tumor and normal sequencing assay. Risk ratios (RR) and 95% CI of testing were estimated using Poisson regression. The prevalence of pathogenic variants and variants of uncertain significance (VUS) was generated for tested patients. RESULTS: Of the 758 eligible patients, 262 (34.6%) were tested. In fully adjusted models, adoption of genomic testing increased over time (2019 v 2016: RR, 2.06 [95% CI, 1.49 to 2.86]), whereas older age (ages 15-19 v <5 years: RR, 0.69 [95% CI, 0.52 to 0.91]), female versus male sex (RR, 0.81 [95% CI, 0.66 to 0.98]), and living in a rural versus urban/suburban area (RR, 0.60 [95% CI, 0.38 to 0.96]) were independently associated with lower genomic testing. Compared with solid tumors, lymphomas were less likely (RR, 0.49 [95% CI, 0.24 to 0.98]) and CNS tumors were more likely (RR, 1.70 [95% CI, 1.37 to 2.12]) to be tested. Among the tested patients, the prevalence of pathogenic variants and VUS did not differ by race/ethnicity or neighborhood socioeconomic status. CONCLUSION: Our work highlights the need for more equitable genomic testing practices in pediatric cancer care to reduce clinical outcome disparities and demonstrates how the population-based integrated database generated for the UCSF NCCR serves as a valuable resource for advancing epidemiologic research for patients with pediatric cancer.