Adult T-cell leukemia-lymphoma (ATL) is a unique T-cell cancer first described in Japan. We estimate that more than 200 patients a year have been detected in Kyushu. The surface phenotype of ATL cells characterized by monoclonal antibodies is T3+, T4+, T8-, T11+, and Tac+. In all cases the serum is positive for anti-human T-cell leukemia (lymphotropic) virus (HTLV-I) antibodies and the ATL cells contain the proviral DNA of HTLV-I. Variations in the clinical features of atypical cases suggest a division of the spectrum of ATL into five types: acute (prototypic), chronic, smoldering, crisis, and lymphoma. Screening of the sera from healthy adults for presence of the anti-HTLV-I antibodies revealed that 3.6% of healthy individuals in Kumamoto Prefecture, which is located in the middle of Kyushu, were HTLV-I carriers. The percentage of positivity increased with age and was higher in females than in males. It varied from town to town, ranging from 0 to 17.6%. Family studies showed that the routes of natural infection of HTLV-I are from mother to child and also from husband to wife. The third route is blood transfusion. The borderline between the healthy carrier state and smoldering ATL remains unclear. In the endemic areas smoldering ATL is frequently diagnosed in patients with fungus infection of the skin, chronic lymphadenopathy, interstitial pneumonitis, chronic renal failure, and stronglyloidiasis. In addition our experiences with a concurrence of lymphoma-type ATL in three sisters and spontaneous remissions in a patient with chronic ATL are cited.
Presented at the HTLV Symposium, December 6 and 7, 1984. Bethesda, MD. This study was supported by grants from the Ministry of Education, Science and Culture and from the Ministry of Health and Welfare of Japan.