Retrovirus‐associated adult T‐cell leukemia‐lymphoma: An epidemiologic study of five cases among Hawaii‐born offspring of migrant Japanese

Adult T-cell leukemia-lymphoma (ATLL) is a distinct clinicopathologic entity etiologically linked to HTLV-I infection. We have identified five cases of retrovirus-associated ATLL among Hawaii-born first generation offspring (nisei) of migrant Japanese. Four patients were offspring of migrant Japanese (issei) who emigrated to Hawaii from Okinawa, an HTLV-I endemic area. The fifth patient was born of parents who emigrated to Hawaii from Fukushima and Miyagi prefectures, HTLV-I nonendemic areas. Epidemiologic implications and family studies with regard to HTLV-I antibody testing of the index cases are discussed. The high rate of HTLV-I antibody seropositivity among family members and relatives indicates that the risk of acquiring HTLV-I infection and of developing ATLL persists long after migration. Documentation of ATLL among offspring of Japanese immigrants to Hawaii is an important observation because it confirms the potential for long latency between putative exposure to virus and the development of overt disease. Changing marriage patterns among the Hawaii-Japanese may weaken the risk of vertical virus transmission to the descendents of migrants from southern Japan, while increasing the risk to children born of mixed marriages. In addition, blood products derived from high-risk donors will constitute a continuing hazard if they are not subject to screening.