Necrotizing sarcoid granulomatosis mimicking an intracranial neoplasm: clinicopathologic features and review of the literature.

We present a unique case of biopsy-proven necrotizing sarcoidosis involving the central nervous system (CNS) in a 52-year-old woman. The patient presented with a 3-month history of left-sided headache and sharp, shooting pains on the left side of her face. She also has a previous history of sarcoidosis, histopathologically confirmed on parotid gland biopsy 24 years before. Imaging studies of the present lesion revealed a 1.8 x 1.4-cm mass in the left temporal lobe with signal intensity suggestive of meningioma or low-grade glial neoplasm. Surgical resection was initiated, and intraoperative consultation with frozen sections revealed granulomata. The lesion was biopsied, and surgical intervention was terminated. Permanent sections failed to reveal bacteria, mycobacteria, fungi, or foreign bodies. A diagnosis of necrotizing neurosarcoidosis was rendered. The patient was administered steroid therapy and clinically responded favorably. At the most recent follow-up almost 2 years later, there was no evidence of recurrence or progression. Necrotizing sarcoidosis has been reported most commonly in the lungs and rarely in other organ systems. We report the first histologically proven case involving the CNS as well as a rare example of sarcoidosis and necrotizing sarcoid granulomatosis in the same patient. Sarcoidosis and its necrotizing variant should be considered in the differential diagnosis of a granulomatous mass lesion involving the CNS, particularly in the context of a history of systemic disease.