Sinus histiocytosis with massive lymphadenopathy: response to cyclophosphamide therapy.

A patient with sinus histiocytosis with massive lymphadenopathy is described. After attempts to control lymph node size and constitutional symptoms with corticosteroids were unsuccessful with radiation therapy and nonsteroidal anti-inflammatory drugs, the patient was treated with two courses of low doses of oral cyclophosphamide therapy. He remains in complete remission 15 months after therapy was discontinued.