Neurofibroma originatig in the peripheral facial nerve located in the parotid gland is a very rare disease which has been reported by Maxwell(1951) and Michael(1987). This tumor must be diagnosed differently than schwannoma and neurogenic tumors.
When
this lesion develops in the parotid region, parotid gland tumor must be rulled out. It can be diagnosed with difficulty using aspiration, and conclusively diagnosed using histological biopsy.
This benign but clinically malignant tumor has no capsule and multiple outgrowth with 'bag of worms' fingings on palpation, which extends across the neuronal axon without degeneratve changes. This lesion lesion can be manifested as a part of
neurofibrtomatosis, solitary or multiple tumor with more frequent sarcomatous degenerations than schwannoma. But schwannoma which has the characteristics of circumscribed, well-encapsulated findings, pretends to push the axon eccentrically with
cystic
orhemorragic degenerative changes in a solitary lesion. To excise this poorly encapsulated neurofibroma, en bloc resection containing nerve fibers in inevitable, nad nerve preservation procedures are unattainable. So intraparotid facial nerve
neurofibroma cannot be confirmed by preoperative evauluation, and managements, whehter any nerve preservation methods can be chosen or not, is very difficult and depend on size, location, and degree of the outgrowth. Until recent days, primary
neurogenic tumors in peripheral facial nerve origin are almost all reported as Schwannoma except for 2 previous cases.
The authers reported one case of solitary nerofibroma orginating in the buccal branch of the facial nerve. This was excised completely under microscopic magnification without any complications.
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