Incidence of leukemia in Asian migrants to the United States and their descendants

Objective: To generate clues regarding the causes of leukemia we compared leukemia incidence rates among Asian-American immigrants and their descendants to those of United States-born whites. Methods: 535 Asian and 6629 white residents diagnosed with leukemia were identified through the Surveillance, Epidemiology and End Results Program during 1973 through 1986 in Hawaii, San Francisco/Oakland, and western Washington. A special tabulation of the 1980 US census was used to estimate the size and composition of the population at risk in these three areas. Results: The incidence of leukemia, either considered as a whole or as individual types, did not appreciably vary between US-born and foreign-born Asian Americans. For all forms of leukemia combined the rates per 100,000 person-years among males were 6.5 for foreign-born Chinese, 7.4 for foreign-born Japanese, and 7.5 for foreign-born Filipino as compared to 7.5 for US-born Chinese, 7.1 for US-born Japanese, and 5.4 for US-born Filipino. The rates in foreign-born Asian females and US-born Asian females were also similar. Asian Americans had a lower incidence of leukemia than US whites (rate of 13.3/100,000 person-years), particularly for chronic lymphocytic leukemia. Conclusions: Irrespective of birthplace, Asian Americans possess one or more characteristics which make their risk for leukemia less than that of US whites.