Appearance of Sezary-like Atypical Lymphocytes in the Regressing Lesion of Juvenile Xanthogranuloma: It's role in the spontaeous regression

Abstract

A case of juvenile xanthogranuloma of the skin was sequentially biopsied for 10 months. In the electron microscopic examination of the regressing lesions, we observed that cells with highly indented nuclei, Sézary-like cells, were in close apposition to vacuolated degenerating histiocytes in many foci. In immunohistochemical stain, the number of UCHL-1+ cells were increased in regressing lesions compared with early lesions. We speculate that these Sézary-like atypical lymphocytes may be closely related to the spontaneous regression of juvenile xanthogranuloma.