Differential inequality trends over time in survival among US children with acute lymphoblastic leukemia by race/ethnicity, age at diagnosis and sex
A partir des données des registres américains des cancers sur la période 1975-2010, cette étude analyse l'évolution des disparités ethniques dans la survie de patients pédiatriques atteints d'une leucémie lymphoblastique aiguë avant l'âge de 19 ans
Background: It is unclear how inequalities in survival among children with acute lymphoblastic leukemia (ALL) have changed over time in different race/ethnicity groups. Methods: Children diagnosed with a first primary malignant ALL at age 0-19 years in 1975-2010 in the nine Surveillance, Epidemiology and End Results cancer registries were included. Cumulative ALL mortalities were compared, and multivariable Cox regression analyses were applied to estimate ALL mortality hazard ratios (HRs) associated with race/ethnicity, age at diagnosis and sex, adjusting for each other, within each diagnosis period (1975-83, 1984-91,1992-99, and 2000-10). Results: Compared to non-Hispanics-Whites (NH-Whites), the HR in non-Hispanic-Blacks (NH- Blacks) dropped to 1.21 (95% CI, 0.74-1.96) in 2000-10 from the largest inequality in 1984-91 (HR=2.09, 95% CI, 1.57-2.79); the HR in Hispanics increased, however, from 1.28 (95% CI, 0.98-1.66) in 1975-83 to 1.95 (95% CI, 1.48-2.58) in 2000-10. Asian/Pacific Islanders (APIs) and American Indian/Alaska Natives (AIANs) had HRs of 1.39 (95% CI, 0.92-2.11) and 2.31 (95% CI, 1.13-4.74), respectively, in 2000-10 with non-statistically significant increases over time. In 2000-10, compared to NH-White counterparts, NH-Blacks and APIs diagnosed at 1-9 years, Hispanics diagnosed at 1-9 and 10-19 years, and AIANs diagnosed at 10-19 years all had about twice the ALL mortality hazard rates ; inequality was observed among API boys (HR=1.61, 95% CI, 1.00-2.60) but not API girls. Conclusions: Survival inequalities changed differently across subgroups of children with ALL. Impact: Underlying causes of the differential trends need to be examined, such that targeted interventions can be developed to reduce inequalities.