Acute Leukemia in Adult Hispanic Americans: Differences in Incidence Rates by Nativity

The incidence pattern of adult acute leukemia (AL) in Hispanics is distinct, with increased B-cell acute lymphoblastic leukemia (ALL) and acute promyelocytic leukemia (APL) and decreased non-APL acute myeloid leukemia (AML). To better understand genetic versus environmental contributors, we assessed AL incidence rates in a population of adult California Hispanics according to birthplace. Using data from California AL patients ≥20 diagnosed between 2000-2009, incidence rate ratios (IRR) were employed to compare incidence rates of AL in foreign- versus United States (US)-born Hispanics. Compared to whites, Hispanics had increased incidence rates of B-cell ALL and APL, IRR2.13 (1.93-2.35) and 1.33 (1.12-1.57), respectively. No nativity differences in B-cell ALL were noted. Foreign-born Hispanics had a higher incidence rate of APL versus US-born Hispanics (IRR 1.79, 1.11-2.94). For adult Hispanics, increased B-cell ALL incidence rates may be due to heritable genetic factors; increased APL incidence rates may be due to as yet unknown environmental exposures.