Primary intracerebral Rosai-Dorfman disease

Sinus histiocytosis with massive lymphadenopathy (SHML), also known as Rosai-Dorfman disease (RDD), is an idiopathic histiocytic disorder of lymph nodes and extranodal sites. Central nervous system (CNS) manifestations, particularly in the absence of nodal disease, are rare. Intracranial RDD clinically and radiologically resembles meningioma, and histologic examination is essential for a definitive diagnosis. We report four patients with RDD primary to the CNS without evidence of other sites of involvement, review the literature, and discuss the clinical manifestations, pathology, treatment and outcome.