Primary cutaneous plasmacytoma: report of a case with review of the literature.

Primary cutaneous plasmacytoma (PCP) is a rare cutaneous B-cell lymphoma. We report a new case of PCP and review data published in the literature. A 55-year-old man presented with 2 erythematous plaques on the upper trunk, showing histologic and immunohistochemical features of PCP. Staging investigations excluded extracutaneous manifestations of the disease. The patient was treated with melphalan and prednisone associated with local radiotherapy. Twenty-four months after the first presentation he is alive and well. Only 29 cases of PCP have been reported in the last 50 years. The main prognostic factor seems to be the clinical presentation (solitary vs multiple lesions). Solitary lesions of PCP may be treated conservatively by surgical excision or local radiotherapy.