Castleman's Disease with Cutaneous Involvement Manifestating as Multiple Violaceous Plaques on Entire Body.

Castleman's disease (CD) is an uncommon B-cell lymphoproliferative disorder characterized by lymph node hyperplasia with vascular proliferation. Cutaneous involvement in CD is rare. A 65-year-old man presented with a 7-year history of gradually developing multiple reddish to violaceous indurated plaques on the scalp, trunk, and legs. On physical examination, there were palpable enlarged cervical, axillary, and inguinal lymph nodes. Laboratory examination revealed anemia, thrombocytosis, hyperproteinemia, hypoalbuminemia, and polyclonal hypergammaglobulinemia. An inguinal lymph node biopsy and a skin biopsy were performed and the patient was diagnosed with the plasma cell type of CD. Chemotherapy was started and the lesions have responded to treatment.