Author(s): Kattner KA
BACKGROUND: Sinus histiocytosis with massive lymphadenopathy was originally described by Rosai and Dorfman in 1969. It usually presents with bilateral painless cervical lymphadenopathy. In extremely rare circumstances, the CNS can be affected. Only 21 prior cases of intracranial involvement have been reported. CASE REPORT: A 33-year-old white male presented with a 2-week history of progressive cephalgia. The patient underwent MRI testing that revealed an enhancing mass in the right parasagittal region with associated edema. Preoperative diagnosis was right parasagittal meningioma. The patient underwent craniotomy with complete resection of the mass. Histopathology was compatible with Rosai-Dorfman disease (RDD). CONCLUSION: Rosai-Dorfman disease is rarely found intracranially; however, its ability to mimic meningioma as well as other pathologies underlines its importance. With so few reported cases of intracranial involvement, more experience will be necessary before this clinical presentation and prognosis can be clearly outlined.