Cutaneous T cell lymphomas: mycosis fungoides, Sezary syndrome and HTLV-I-associated adult T cell leukemia (ATL) in Mali, West Africa: a clinical, pathological and immunovirological study of 14 cases and a review of the African ATL cases

Abstract

Cutaneous T cell lymphomas (CTCL) are rare lymphoproliferative diseases, which are frequently suspected to be of viral origin. As very few data were available concerning cutaneous T cell lymphomas in tropical Africa, we undertook a clinical, histopathological, immunological and viro-molecular study of patients with a clinical diagnosis of cutaneous lymphoma, in Bamako, Mali. While prior to this study, no case of CTCL had been reported in this country, 14 patients (five women, nine men; mean age 58 years) with a diagnosis of cutaneous lymphoma were seen over a period of 30 months (1992-1994) in the only dermatological department in Mali. Clinically, the most frequent pattern was an infiltrated erythrodermia similar to Sezary syndrome. Nodular lesions and/or plaques were rarely observed. All these cutaneous tumors were T cell lymphoproliferations, only one expressing the CD8 + antigen. A comprehensive analysis of all the available data permitted characterization of three cases of adult T cell leukemia/lymphoma (ATL) associated with HTLV-I (one definitive case, of leukemic type, with demonstration of clonal integration of HTLV-I proviral genome and two probable ATL cases), three cases of Sezary syndrome (SS), two cases of mycosis fungoides (MF) and five cases of pleomorphic cutaneous lymphoma. In one case, the differentiation between MF and pleomorphic cutaneous lymphoma could not be established. HTLV-I serological and/or molecular markers were restricted to the three ATL cases. From the unique definitive ATL case, a T cell line was established from culture of peripheral blood mononuclear cells and sequence analysis of the env gene and the U3-LTR region demonstrated that the virus present in this patient belonged to the cosmopolitan subtype A. Thus, we report here the first evidence of HTLV-I infection and associated ATL in Mali. This is the second ATL case described for the whole Sahelian region (one ATL of the lymphoma type was reported previously in a Mauritanian patient). Furthermore, we demonstrate that the main types of CTCL described in Europe and North America are also present in this African area and that the prevalence of these diseases is greatly underestimated in such regions. Furthermore, no association was observed between HTLV-I/II infection and SS, MF or pleomorphic cutaneous lymphoma in Mali in contrast to other studies.

Description of a “Trans-Saharan” Strain of Human T-Lymphotropic Virus Type 1 in West Africa

“…The presence of HTLV-1 has been reported in various Sahara countries, particularly Morocco, 23 Tunisia, 24 Egypt, 25 Mali, 11 Mauritania, and Algeria, and LTR analyses of some of these isolates have identified the North African subgroup of the cosmopolitan subtype (HTLV-1aD). 6 The phylogenetic analyses of all the cosmopolitan isolates from our patients, together with other previously described isolates from Guinea Bissau and Senegal, 12,26 showed that they belonged to the HTLV-1aD subgroup.…”

“…7 HTLV-1 is widespread in sub-Saharan Africa, particularly in West and Central Africa. In West Africa, the reported rates of seropositivity for anti-HTLV-1 antibodies vary from 1% to more than 5% among blood donors and/or pregnant women in Ghana, 8 Benin, 9 Burkina Faso, 10 Mali, 11 Senegal, 12 Nigeria, 13 and Guinea Bissau. 14 The prevalence of HTLV-1 infection in Guinea Bissau is one of the highest in Africa.…”

Global epidemiology of HTLV-I infection and associated diseases

“…A few years later, it was described in Caribbean immigrants living in United Kingdom (Catovsky et al, 1982) and afterwards reported in other endemic areas, including the Caribbean region (Gibbs et al, 1987;Hanchard, 1996), Africa (Fouchard et al, 1998) and South America (Matutes et al, 1994;Gerard et al, 1995). Following the initial description of ATL ) the epidemiologic clustering of ATL within certain age groups in localized areas of southern Japan instigated the interest by Japanese investigators that the malignancy could be virally induced.…”

Seroprevalence and Molecular Epidemiology of Human T-Cell Leukemia Virus Type 1 (HTLV-1) and HTLV-2 in Blood Donors from Dakar, Senegal

“…Moreover, most of the epidemiological studies have been performed in hospitalized patients or in individuals at risk for acquiring HTLV-1 (prostitutes, human immunodeficiency virus [HIV]-infected patients, etc.) or in rural populations (2,10,15,34,35). Therefore, very few data have been reported thus far for large populations of blood donors from west or central Africa (1,9,12).…”