Granulomatous slack skin in childhood.

Granulomatous slack skin is an uncommon cutaneous T-helper cell lymphoma closely related to mycosis fungoides. To the best of our knowledge this disease has not been previously described in children. We report on an 11-year-old boy who presented with painless slack skin masses in the neck, right axilla and arm, anterior wall of the abdomen, both inguinal regions, and the malleolar and dorsal aspects of the feet. The disease started 3 years earlier with erythematous lesions on the neck and wrists. Histologic examination of a specimen from the abdominal mass revealed an extensive lymphoid infiltrate with scattered multinucleated giant cells extending from the papillary dermis to the subcutis. The lymphoid cells showed the following immunophenotype: CD43+ (MT1), CD45+, CD45RO+, CD20-. The phenotype of the giant cells was lysozyme positive, CD68+ and Mac387-. The tumoral lymphoid cells had clonal rearrangement for the gene of the beta chain of the T-cell receptor (C beta TCR). The disease could be controlled with systemic glucocorticoids. Due to the presence of many histiocytes arranged in aggregates in the papillary and mid-dermis, this case was initially considered to be a cutaneous form of histiocytosis. We recommend deep and extensive biopsies in patients with slack skin disease.