CLUSTERING AND CLINICAL DIVERSITY OF ADULT T-CELL LEUKEMIA LYMPHOMA ASSOCIATED WITH HTLV-I IN A REMOTE BLACK-POPULATION OF FRENCH-GUIANA/

An epidemiological study was performed in French Guiana (population 11 5,000) to determine the prevalence and incidence of adult T-cell leuke mia/lymphoma (ATL) associated with human T-cell leukemia/lymphoma viru s type I (HTLV-I). From January 1990 to December 1993, all suspected c ases of ATL were enrolled in this study, and their clinical, epidemiol ogical and immunovirological features were analyzed. Out of the 19 sus pected cases, 18 were considered as ATL associated with HTLV-I (8 acut e forms, 8 lymphoma types and 2 smoldering cases). Before this study, only 2 ATL cases had been reported in French Guiana over a 10-year per iod. This demonstrates that the number of ATL cases is greatly under-e stimated in most tropical HTLV-I endemic areas unless a specific disea se search is performed. The mean age of the patients was 41 years. Whi le HTLV-I antibodies were present in all cases, molecular studies demo nstrated a clonal integration of HTLV-I in the tumoral cells in 7 case s out of the 9 tested. Fifteen patients died within a year of diagnosi s. The crude incidence rate of ATL in French Guiana is around 3.5/100, 000/year, a situation similar to that found in the Caribbean and in HT LV-I-endemic regions of Japan. However it reaches around 30/100,000/ye ar (highest incidence ever described)in a small remote ethnic group of African origin (around 6200 inhabitants). Possible causes of ATL clus tering in this ethnic group are presented. (C) 1995 Wiley-Liss, Inc.