Cutaneous lesions in hairy-cell leukemia. Case report and review of the literature.

A patient is described in whom cutaneous lesions were the initial manifestation of hairy-cell leukemia. Touch preparations made immediately on removal of a 3-mm punch biopsy specimen of the cutaneous lesions revealed acid-phosphatase positive, tartrate-resistant staining in the leukemic cells, and helped to establish the diagnosis. Specific eruptions occur in approximately 7% of patients with hairy-cell leukemia, appearing grossly as disseminated, erythematous maculopapules, with a perivascular mononuclear leukemic cell infiltrate seen microscopically. A review of the English literature indicates that cutaneous manifestations are not generally recognized as a diagnostic source in individuals with hairy-cell leukemia, and biopsy is seldom undertaken.