Head and Neck Nerve Sheath Tumors: A 10-Year Evaluation in Iran

  Background and Objective: Approximately 45% of benign peripheral nerve sheath tumors (PNST) occur in head and neck regions. Malignant peripheral nerve sheath tumors (MPNST) are less common and only 8-15% of these tumors occur in head and neck region. In this study, we aimed at evaluating the demographic characteristics, pathologic findings, locations, main clinical presentations and family history of these tumors in head and neck regions.  Patients and Methods: In a cross sectional and retrospective study, we analyzed head and neck peripheral nerve sheath tumors in patients who referred to Amir-Aalam Hospital affiliated to Tehran University of Medical Sciences for 10 years (1996 to 2005). Results: There were 113 cases with a kind of nerve sheath tumor; the female/male ratio was 1.09. The frequency of schwannoma, neurofibroma and MPNST was 66.37%, 30.1% and 3.53%, respectively including 39 cases of acoustic neuroma, 18 cases of cervical nerve trunk involvement, 12 cases of facial nerve involvement, 11 cases of the 10th cranial nerve PNST and only one case of cervical sympathetic nerve involvement. Conclusion: Schwannomas are the most common types of PNSTs seen in head and neck regions, and aucoustic neuroma comprises the majority of them. About 25- 45% of extracranial schwannomas also occur in head and neck regions that usually present a slow growing of the mass lesion and various mass effects. Although neurofibroma and MPNSTs are less common, they must be kept in mind as differential diagnoses of other benign and malignant lesions in this region.