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[Olfactory (subfrontal) schwannoma: case report and literature review].

BACKGROUND
Olfactory nerve schwannomas are extremely rare. Their origin is still unclear, since olfactory nerve has no Schwann cells. There are about 70 case reports of olfactory nerve schwannoma in the world literature. Original articles devoted to this issue are currently absent.


RESULTS
We present a 55-year-old patient with olfactory nerve schwannoma who underwent surgery at the Federal Center of Neurosurgery in Novosibirsk. MRI revealed extracerebral mass lesion of anterior cranial fossa base with left-sided lateralization resembling meningioma of the olfactory fossa. The patient underwent microsurgical resection of mass lesion of anterior cranial fossa base through left-sided lateral supraorbital craniotomy. The tumor macroscopically resembled schwannoma. Total resection was carried out. Considering morphological structure and immunomorphological characteristics, we verified schwannoma Grade 1.


CONCLUSION
Olfactory nerve schwannomas are rare tumors with benign histological structure. Relapses after total resection are unlikely. However, further research of this rare pathology and long-term postoperative follow-up are required.