Sinus histiocytosis with massive lymphadenopathy and epidural involvement.

Sinus histiocytosis with massive lymphadenopathy (SHML) was recognized as a new clinical-pathological entity in 1969. Up to the present 134 cases have been described. The disease is characterized by prominent cervical lymph node enlargment. Microscopic features include marked dilatation of sinuses with intrasinusal histiocytes and lymphophagocytosis. About 70% of the patients reported were affected during the first 2 decades of life. The disease is held to be benign on account of spontaneous resolution in some patients. A follow-up survey of 72 patients showed disappearance of the symptoms 10 years after the original diagnosis in 24 patients. In 42 patients the disease still persisted 6 months to 21 years later. Six patients died, but only one of them as a result of the disease. Extranodal involvement was seen in the orbit, eyelid, respiratory tract, skin, bone, salivary glands, and testis. In two cases, one of which will be reported here, paraparesis resulted from infiltration of the epidural space. Treatment with prednisolone was tried in some cases with excellent results. In our case treatment with prednisolone and vinblastine resulted in the disappearance of the neurological symptoms.