Nerve sheath myxoma (neurothekeoma) in the tongue of a newborn.

Nerve sheath myxoma is a benign peripheral nerve sheath tumor that rarely occurs in the oral cavity; experience with these lesions is therefore limited. The lesion described in this report appeared clinically as a gradually enlarging, painless growth arising on the tongue of a newborn girl. Microscopically, the lesion was characterized by nodules of spindle-shaped cells with abundant myxoid stroma. Immunohistochemical studies were consistent with a nerve sheath neoplasm.