Follow-up of asymptomatic HTLV-I carriers among blood donors in Kyushu, Japan.

We examined mortality from adult T-cell leukemia/lymphoma (ATL/ATLL) and other diseases alleged to be associated with human T-lymphotropic virus type I (HTLV-I) among anti-HTLV-I antibody-positive blood donors in Kyushu, Japan. During 1984-87, a total of 3,991 blood donors aged 40 years or over were followed from the date of donation to the date of death or the end of the study. Crude mortality rates from ATL (with 95 percent confidence intervals) were 68 per 100,000 (13-202) for males and 36 per 100,000 (3-132) for females. The rates were underestimated by approximately 50 percent because of self-selection and short observation periods. Neither death rates from other cancers nor death rates from all cancers were elevated.