Schwannomas of the facial nerve as differential diagnosis to parotist tumors

Introduction:

Neurinomas (correct: schwannomas) of the facial nerve represent a rare entity of tumors of the regio parotidea. Schwannomas are slowly growing benign tumors originating from the Schwann's cells, which can occur at any age, but frequently show an association with neurofibromatosis. They impress intraoperatively similar to a fibroma. Through displacing growth, they can rarely cause facial nerve paresis.

Case:

We demonstrate the case of a 37-year-old patient who was presented to us with a swelling of the regio parotidea that had existed for almost 7 years. There was no facial nerve paresis at the time of first contact. Sonographically a cystoid structure of approx. 3 × 2 cm size without vascularization was observed. In order to specify the diagnosis, a cMRT was performed on which the tumor was hyperintense and a suspected diagnosis of a schwannoma was made.

With ultimately unclear swelling we performed a lateral parotidectomy on the patient. Intraoperative surgery presented a tumorous compartment with aspects of a fibroma from which the nerve could not be safely separated. In the frozen section diagnosis, the suspected diagnosis of a schwannoma could then be confirmed. A total tumor resection was not performed, as discussed with the patient beforehand.

Conclusion:

The prognosis of the schwannoma is basically good, but it must be assumed that a paresis can occur in the course of the disease if there is no resectability. Patients with appropriate histology should be examined for neurofibromatosis. Schwannoma remains a rare differential diagnosis of a tumor of the regio parotidea, which should be considered.

Publication History

Publication Date:
23 April 2019 (online)