Leukemia survival in children, adolescents, and young adults: influence of socioeconomic status and other demographic factors

OBJECTIVE: In California, leukemia represents ~35, 5, and 2% of all cancers in children (aged 0–14), adolescents (15–29), and young adults (30–39), respectively. Poorer survival has been previously noted in individuals residing in lower socioeconomic status (SES) neighborhoods. We explored the relationship between SES and survival as modified by age and race/ethnicity using data from the California Cancer Registry. METHODS: A total of 7,688 incident cases of first primary leukemia diagnosed during 1996–2005 in individuals aged 0–39 at diagnosis were included in this study. Univariate analyses of overall survival were conducted using the Kaplan–Meier method and multivariate survival analyses were performed using Cox proportional hazard regression to estimate hazard ratios. RESULTS: Multivariate analyses showed that overall survival and lymphoid cancer–specific survival was reduced in those individuals aged 15–39 compared to children aged 0–14. Although shorter survival was observed in non-whites, an association between lower-SES neighborhood and shorter survival was significant only for non-Hispanic whites (NHWs) (p value for trend <0.05). Lack of insurance was significantly associated with shorter survival for all race/ethnicities examined except Asian/Pacific Islanders (p value < 0.05). CONCLUSION: Lower survival in individuals diagnosed with leukemia was observed in adolescents and young adults compared to children and in non-whites compared to NHWs. Further, the independent effects on survival of both low SES and lack of insurance at diagnosis persisted after adjustment for demographic variables and varied across race/ethnicities.