Isolated intracranial Rosai-Dorfman disease: report of two cases and a review of the literature.

Rosai-Dorfman disease (RDD) is a rare but well-recognized idiopathic histioproliferative disease affecting the systemic lymph nodes. It is characterized by an unusual proliferation of histiocytic cells. Intracranial localization is a rare manifestation of RDD. The clinical and radiological differentiation from meningiomas is difficult, and can only be achieved after histological examination. This entity should be considered in the differential diagnosis of dural based lesions mimicking meningioma. We report 2 cases of isolated intracranial RDD. The first patient had a large frontal lesion in addition to smaller multiple intracranial lesions. The second patient had only one parasagittal lesion. The diagnosis was confirmed on histopathological examination after surgical excision. The pertinent literature is also reviewed.