10084-RC-2 A case of neurosarcoidosis mimicking multiple meningiomas

Abstract Background As differential diagnoses for multiple extra-axial mass lesions, meningioma, metastastses, and inflammatory diseases should be considered. We report a case of neurosarcoidosis mimicking multiple meningiomas. Case presentation A 64 year-old man who did not have any particular previous medical history presented with visual disturbance revealing central scotoma on the left side one month before initial consultation. Magnetic resonance imaging demonstrated the gadolinium-enhanced tumor in the left sphenoid wing spreading along the tentorial edge, accompanied with multiple tumors along the falx, the parasagittal, and the convexity, consisting of seven extra-axial tumors. With preoperative diagnosis as multiple meningiomas, the tumor in the left sphenoid wing was removed for the purpose of preservation of the visual acuity as well as histological diagnosis. The tumor was totally removed via devascularization from the attached dura, followed by internal debulking and dissection carefully from the adjacent structures including internal carotid artery, the optic nerve, and the oculomotor nerve. The tumor adhered tightly to the surrounding neuronal structure was very hard with abundance of vasculatures supplied from the pial artery. The intraoperative diagnosis by rapid frozen section was not contradict to meningioma without malignancy, however final histological diagnosis by permanent section turned out to be sarcoidosis. Postoperatively, the patient was suffered from transient oculomotor nerve palsy, but improved by postoperative adjuvant therapy with steroid. Discussion Since neurosarcoidosis is very rare disease, accurate diagnosis preoperatively is would be difficult. To avoid surgical insult to patients who undergo radical resection, biopsy might be adequate to confirm histological diagnosis for decision of postoperative adjuvant therapy for multi-focal lesions, since steroid very effective for neurosarcoidosis. Conclusion We learned importance of differential diagnosis to select appropriate surgical strategy for steroid-responsive disease such as inflammatory and granulation lesions including neurosarcoidosis.