Abstract
Rosai Dorfman disease (RDD) is rare histiocytic disease with unknown etiology that typically presents with painless cervical lymphadenopathy. The disease is also known as sinus histiocystosis with massive lymphadenopathy (SHML). The normal functioning of lymph glands is disturbed due to significant enlargement of the lymphatic sinuses. Sinus hystiocytes contain cytoplasmic fat and strongly positive S100 protein CD68 and CD14 can be positive. Forty percent of patients have extra nodal involvement. The prognosis of the disease is usually good. However, if accompanied by immunologic abnormalities young age, extra nodal involvement (especially in the kidney or, liver), and the prognosis is poor. Regarding treatment, the disease often has spontaneous remission; therefore, observation is essential. No treatment modalities are superior to over another. In this article, we present a male patient who was diagnosed as having extra nodal RDD with skin and soft tissue involvement, who was followed up for four years.