Expression of selected T-cell antigens in the skin infiltration in primary cutaneous T-cell lymphomas.

Skin biopsy specimens obtained from 16 patients with mycosis fungoides (MF) were examined immunohistochemically to assess phenotype of T-cells. Cases of benign chronic skin disorders (BCD) were included in control group. Examination of skin biopsies obtained from patients with MF revealed aberrant immunophenotypes of T-cells (loss of one or more of T-cell markers CD7, CD5, CD8, and rarely CD3). The expression of CD1a antigen both in the dermis and epidermis of the studied groups was similar and normal. No correlation between this loss of antigenicity and the prognosis was observed. These disturbances were seen in most of the cases of the early MF, but not seen in inflammatory skin diseases. In conclusion, the presence of aberrant immunophenotype of T-cells in skin infiltration may be useful in the diagnosis and differentiation of MF.