Disparities in survival improvement for U.S. childhood and adolescent cancer between 1995 and 2019: An analysis of...

Although treatment advances have increased childhood and adolescent cancer survival, whether patient subgroups have benefited equally from these improvements is unclear.

Data on 42,865 malignant primary cancers diagnosed between 1995 and 2019 in individuals ≤ 19 years were obtained from 12 Surveillance, Epidemiology, and End Results registries. Hazard ratios (HRs) and 95 % confidence intervals (CIs) for cancer-specific mortality by age group (0-14 and 15-19 years), sex, and race/ethnicity were estimated using flexible parametric models with a restricted cubic spline function in each of the periods: 2000-2004, 2005-2009, 2010-2014 and 2015-2019, versus 1995-1999. Interactions between diagnosis period and age group (children 0-14 and adolescents 15-19 years at diagnosis), sex, and race/ethnicity were assessed using likelihood ratio tests. Five-year cancer-specific survival rates for each diagnosis period were further predicted.

Compared with the 1995-1999 cohort, the risk of dying from all cancers combined decreased in subgroups defined by age, sex and race/ethnicity with HRs ranging from 0.50 to 0.68 for the 2015-2019 comparison. HRs were more variable by cancer subtype. There were no statistically significant interactions by age group (P_interaction=0.05) or sex (P_interaction=0.71). Despite non-significant differences in cancer-specific survival improvement across different races and ethnicities (P_interaction=0.33) over the study period, minorities consistently experienced inferior survival compared with non-Hispanic Whites.

The substantial improvements in cancer-specific survival for childhood and adolescent cancer did not differ significantly by different age, sex, and race/ethnicity groups. However, persistent gaps in survival between minorities and non-Hispanic Whites are noteworthy.