Subfrontal schwannoma.

Subfrontal schwannoma is a rare disease, which can be mis-diagnosed as an olfactory meningioma or a neuroblastoma, because of similar clinical symptoms and signs and neuroradiological features. Especially for young subjects, olfactory neuroblastoma should be carefully differentiated, since the management strategies for those lesions are significantly different. The craniofacial approach is often needed for the resection of a neuroblastoma. We report a case of 14-year old boy in which olfactory neuroblastoma was suspected prior to surgery, but turned out to be a schwannoma histologically. Molecular genetic examination revealed neither NF2 gene mutation nor loss of heterozygosity of chromosome 22q, unlike common schwannomas.