BACKGROUND: Acute lymphoblastic leukemia (ALL) accounts for 80% of all leukemias diagnosed in children. Although ALL age patterns are consistent across racial/ethnic groups, their incidence and mortality rates are highly variable.We assessed the age-standardized ALL incidence and mortality rates of Puerto Rican Hispanic (PRH) children and compared them with those of US mainland Hispanics (USH), non-Hispanic whites (NHW), non-Hispanic blacks (NHB) and Non-Hispanic Asian or Pacific Islanders (NHAPI).

METHODS: Differences between racial/ethnic groups were assessed by estimating the Standardized Rate Ratio (SRR) for 2010-2014. Secondary data analyses of the Puerto Rico Central Cancer Registry and the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) databases were performed for the 2001-2016 period.

RESULTS: PRH children had 31% lower incidence rates than USH, but 86% higher incidence rates than NHB. In addition, the incidence trends of ALL increased significantly from 2001 to 2016 among PRH and USH, with 5% and 0.9% per year, respectively. Moreover, PRH have a lower 5-year overall survival (81.7%) when compared to other racial/ethnic groups.

CONCLUSIONS: PRH children were found to have disparities in ALL incidence and mortality rates compared to other racial/ethnic groups in the US. Additional research is warranted to identify the genetic and environmental risk factors that may be associated with the disparities observed.

IMPACT: This is the first study reporting the incidence and mortality rates of childhood ALL for PRH and making comparisons with other racial/ethnic groups in the US.