RESUMEN
The direct or indirect involvement of retroviruses with the development of leukaemia/lymphoma has been well established in animals and human.Mycosis fungoides, a rare form of cutaneous T-cell lymphoma, is suspected of having a viral etiology on the basis of certain similarities to adult T-cell leukaemia, which is associated with human T-cell leukaemia/ lymphoma virus type I [HTLV-1] infection. We have searched for HTLV-1, HIV-1 and HIV-2 antigens in the skin lesions and the antibodies in the sera of 3patients with mycosis fungoides. In one patient the skin lesion expressed HTLV-1 related antigen and by PCR we could detect HTLV-1 specific DNA in PBMCs of this patient this result could support the causative role of HTLV-1 in mycosis fungoides