CUTANEOUS HISTOPATHOLOGY OF SEZARY-SYNDROME - A STUDY OF 41 CASES WITH A PROVEN CIRCULATING T-CELL CLONE

Sezary syndrome is an uncommon variant of cutaneous T-cell lymphoma (C TCL) characterized by erythroderma, pruritus, adenopathy, and circulat ing atypical T-lymphocytes with cerebriform nuclei. The definition of Sezary syndrome can be further refined by including only patients with a circulating peripheral blood population of clonal T-cells. We have evaluated 79 skin biopsies from such a group of 41 erythrodermic patie nts with circulating Sezary cells and a clonal population of T-cells d etected by T-cell receptor-beta gene rearrangement on Southern analysi s of peripheral blood mononuclear cells. Histopathologic features cons istent with chronic dermatitis were observed in 26/79 (33%) skin biops y specimens, emphasizing that a non-specific histologic appearance is common. Evidence of CTCL was lacking in 11/41 patients on biopsy of th eir erythrodermic skin. The survival of these patients was not signifi cantly different from 30/41 41 patients in whom skin biopsies revealed changes diagnostic of CTCL, such as a dermal lymphocytic band with at ypical lymphocytes (18/79, 23%) or a mycosis fungoides-like infiltrate (30/79, 38%). This study confirms that non-specific cutaneous histopa thologic findings are common in Sezary syndrome, even when a circulati ng T-cell clone is present. This stresses the need for peripheral bloo d genetic analysis and for multiple or repeat skin biopsies in erythro dermic patients when there is high clinical suspicion of CTCL.