Leukaemic cutaneous T-cell lymphoma-manifesting papuloerythroderma with CD3(-) CD4(+) phenotype.

The leukaemic form of cutaneous T-cell lymphoma, as represented by Sézary syndrome, exhibits erythroderma. We describe here an indolent leukaemic patient with cutaneous T-cell lymphoma, who initially had a nodulo-tumourous eruption with a crop of solid papules, but finally presented with papuloerythroderma. Histologically, the skin lesions showed non-epidermotropic dermal infiltration of atypical lymphocytes with lymphoid follicles and a granulomatous change. The circulating malignant CD4(+) CCR4(+) T cells lacked the expression of T-cell receptor and did not respond to concanavalin A. The unresponsiveness of T cells to the T-cell mitogen may be associated with the non-epidermotropic behaviour of the tumour cells and the initially non-erythrodermic eruption.