Intracranial Rosai-Dorfman disease.

Rosai-Dorfman disease (RDD) is a rare histioproliferative disorder that only occasionally involves the central nervous system. We present the diagnosis and treatment of five patients with intracranial RDD. The patients were preoperatively misdiagnosed as meningioma or eosinophilic granuloma. All five patients were treated by total or subtotal surgical resection and none of them experienced recurrence. Histopathological examination showed a characteristic emperipolesis, the lymphocytes were engulfed in the S-100 protein and CD68 positive histiocytes, with negative expression of CD1a. Preoperative diagnosis of intracranial RDD is still challenging because the lesion is usually a dural-based lesion that mimics a meningioma. Surgical resection is an effective treatment and radiotherapy, steroid and chemotherapy has not demonstrated reliable therapeutic efficiency.