Associations Between Race/Ethnicity and US Childhood and Adolescent Cancer Survival by Treatment Amenability.

Importance: Although US cancer survival rates have increased over time, disparities by race/ethnicity remain, including for children and adolescents. Objective: To examine whether racial/ethnic disparities in childhood and adolescent cancer survival vary by cancer type according to relative survival rates (RSRs), a marker for amenability to medical intervention. Design, Setting, and Participants: In a retrospective cohort study using US Surveillance, Epidemiology, and End Results data, 67 061 children and adolescents diagnosed at ages 0 to 19 years with a first primary malignant cancer from January 1, 2000, to December 31, 2016, were evaluated. Data analysis was performed from June 19 to November 3, 2019. Participants were followed up from the dates of diagnosis to cancer death or the end of the follow-up period, whichever came first. Exposures: Race/ethnicity defined as non-Hispanic white, non-Hispanic black, non-Hispanic American Indian/Alaskan Native, non-Hispanic Asian or Pacific Islander, or Hispanic (any race). Main Outcomes and Measures: Cancer amenability was defined using 5-year RSRs for 103 cancer types. Cox proportional hazards regression was used to compute adjusted hazard ratios (aHRs) and 95% CIs for the association between race/ethnicity and cancer survival for high (>85% RSR), medium (70%-85% RSR), and low (<70% RSR) amenability categories. Results: Among 67 061 cancer cases, 36 064 were male (53.8%); most individuals were non-Hispanic white (35 186 [52.5%]) followed by Hispanic of any race (19 220 [28.7%]), non-Hispanic black (7100 [10.6%]), non-Hispanic Asian or Pacific Islander (4981 [7.4%]), and non-Hispanic American Indian/Alaskan Native (574 [0.9%]). Mean (SD) age at diagnosis was 9.66 (6.41) years. Compared with non-Hispanic white children and adolescents, a higher aHR of death was observed for high- than low-amenability cancers for non-Hispanic black patients (high: aHR, 1.59; 95% CI, 1.41-1.80 vs low: aHR, 1.35; 95% CI, 1.24-1.47; P = .002 for interaction) and Hispanic (any race) patients (high: aHR, 1.63; 95% CI, 1.50-1.78 vs low: aHR, 1.16; 95% CI, 1.08-1.25; P < .001 for interaction). Results for other race/ethnicities showed similar patterns but were not statistically significant. Conclusions and Relevance: Racial/ethnic minority children and adolescents were observed to have a higher risk of death than non-Hispanic white children and adolescents, with more amenable cancers having larger relative survival differences. This disparity may be associated with a combination of factors, including differences in access to health care resources.