[Extracranial schwannomas of the Head and Neck: Clinical -approach based on 20 cases]

Background Schwannomas are rare benign tumors originating from the perineural cells forming the myelin layer in the peripheral nervous system (PNS). While well established therapeutic concepts exist for intracranial schwannomas, there is a lack of consistent clinical standards for extracranial schwannomas. Method This retrospective study describes the clinical pathway of 20 patients with histologically proven extracranial schwannomas of the head and neck. The diagnostic and therapeutic strategies for schwannomas are discussed with special emphasis on localization and functional outcome. Results Extracranial schwannomas of the head and neck region mostly originated from the facial nerve (n = 4), vagal nerve (n = 4) or sympathetic chain (n = 3). Most common symptoms were swelling (n = 12) and pain (n = 3). Preoperative imaging included MRI (n = 13), ultrasound (n = 12) and CT (n = 3). Surgical intervention was performed in 18 cases (n = 14 complete extirpation, n = 3 partial extirpation, n = 1 unknown). Regarding completely extirpated schwannomas of motor nerves (n = 10) severing the nerve of origin was more often required in patients with a preexisting functional deficit (3 out of 4 = 75 %) than in patients without preexisting deficits (2 out of 6 = 33 %). Conclusion Representing rare tumors of the head and neck region mostly originating from the facial nerve, sympathetic chain or caudal cranial nerves extracranial schwannomas require a systematic diagnostic and therapeutic approach. Postoperative functional deficits after complete extirpation must especially be anticipated in patients with a preexisting functional deficit.