Management of Facial Nerve Schwannoma in the Accessory Parotid Region

Systematic Review of Intra Parotid Facial Nerve Schwannoma and a Case Report

To evaluate the clinico-epidemiological aspects, pathological features, diagnostic methods, management protocol and functional outcome of the intra-parotid facial nerve schwannoma (IFNS) and to present a case report on intra parotid facial nerve schwannoma. PubMed, ProQuest, Google scholar, Science direct and Scopus were screened for studies. Article selection and data extraction was done by one investigator and other investigator confirmed its accuracy. After abstract and text screening a total of 69 articles were finally selected for the study with the inclusion and exclusion criteria of the systematic review as per PRISMA guidelines. With addition of one case reported to our department. The mean age of diagnosis was 43 ± 16 years with a slight female predominance. The mean duration of the tumour was 29.5 months and the mean size of the tumour on initial diagnosis was 3.6 ± 1.67 cm. Pleomorphic adenoma was the primary diagnosis in 44 cases. Superficial parotidectomy was done in 64 cases followed by resection in 47 cases. Reconstructive treatment was carried out by an end-to-end anastomosis in 3 patients and by facial-hypoglossal anastomosis in 16 patients, GAN cable grafting in 5 patients, a greater auricular nerve graft was done in18 patients and end-to-side interposed sural nerve graft in 8 patients. The type D tumours are treated by extended resection of the facial nerve, which is difficult to reconstruct and also employs a nerve graft that does not often give acceptable recovery of facial function. Facial nerve schwannomas being a rare entity poses a dilemma in diagnosis and management. Managing the lesions is also difficult as intraoperative adherence to the nerve makes a tumour free margin difficult without sacrificing the nerve. At present there is no consensus regarding the management of various types of intra-parotid facial nerve shwannoma.

Intraparotid facial nerve schwannoma: a 17-year, single-institution experience of diagnosis and management

BACKGROUND

Intraparotid facial nerve schwannoma (IFNS) is rare and its definite preoperative diagnosis is challenging.

OBJECTIVE

To improve available knowledge regarding the diagnosis of IFNS and to suggest an appropriate treatment plan.

MATERIAL AND METHODS

We retrospectively analyzed medical records of IFNS patients at our hospital. Inclusion criteria were surgery (from January 2000, to December 2016) for a parotid mass, pathologically diagnosed as a schwannoma.

RESULTS

The study included 42 eligible patients who had undergone tumor resection from 5977 parotid tumor patients. Mostly presented hard-textured (18/39) or medium-textured (15/39), with limited mobility (21/39) mass (three tumors were not palpable). Their facial nerve function outcomes were House-Brackmann Grade I (n = 14), Grade II (n = 7), Grade III (n = 11), Grade IV (n = 5), Grade V (n = 3), and Grade VI (n = 2). Significant differences were noted in results based on different surgical methods used (p = .000) and tumor involvement (p = .002).

CONCLUSIONS AND SIGNIFICANCE

A hard-textured tumor with limited mobility mass in the parotid gland should prompt the diagnosis of a schwannoma. Tumors involving main trunk usually lead to unsatisfactory facial nerve outcomes. Facial nerve preservation should always be essential, and stripping surgery or intracapsular enucleation could be the preferred surgical methods of choice.

Intraoral Schwannomas: Presentation of a series of 12 cases

Introduction: Schwannomas are benign and not very frequent tumors of the peripheral nerves, derived from the nerve supporting Schwann cells. Study Design: Data were collected on the clinical manifestations (sex, age), location, size and symptonts of the lesions as well as the evolution time and the initial (presumption) diagnosis. Results: Twelve patients were documented, with a mean age of 29,5 ± 12,1 years (range 16-50) and a balanced gender distribution. The mean duration of the lesions was 42,17± 45,3 months. The lesion located in the floor of the mouth was the largest tumor, measuring about 4 cm in maximum diameter, while the average size of the 12 schwannomas was 2.04± 1.1 cm. Conclusion: We present 12 oral schwannomas diagnosed and treated over a period of 10 years.

Key words:Schwannomas, oral benign tumor, neurilemmoma.

The intraparotid facial nerve schwannoma: a diagnostic and management conundrum

OBJECTIVES

The aims of the study were (1) to review the management strategy and clinical outcomes of all intraparotid facial nerve (FN) schwannomas (PFNSs) treated at a single tertiary academic center from 1975 to 2010 and (2) to summarize all previously reported cases of PFNS in the international literature.

STUDY DESIGN

A retrospective cohort study and literature review.

METHODS

Fifteen patients were diagnosed and treated at the authors' institution from 1975 to 2010. In addition, 124 published cases were systematically reviewed.

RESULTS

The most common presentation of PFNS was a painless parotid mass with normal FN function. Eccentric, loosely attached intraparotid tumors underwent gross total resection with nerve preservation granting satisfactory postoperative FN function, whereas "inseparable" intraparotid tumors were observed in 8 cases with stable long-term size. Lesions that extended into the fallopian canal underwent complete resection with FN sacrifice and nerve grafting in 10 cases, whereas 1 patient received subtotal resection of the intraparotid portion with stereotactic radiotherapy targeting the intratemporal component.

CONCLUSIONS

Intraparotid FN schwannomas present similar to other primary salivary gland neoplasms, making an early diagnosis challenging. Intraoperative recognition of gross tumor characteristics and early histologic diagnosis with strategic biopsy are critical. Information including tumor location and extent, preoperative FN function, and the gross relationship between the tumor and the FN may guide the surgeon toward an optimal treatment plan emphasizing long-term neurologic preservation.

Surgical management of solitary venous malformation in the midcheek region

OBJECTIVE

The aim of this study was to analyze a single institution's experience of solitary venous malformation (VM) in the midcheek region.

STUDY DESIGN

From 2002 to 2009, a total of 10 consecutive patients with solitary venous malformation in the midcheek region were retrospectively analyzed. Clinical records were reviewed for patient demographic data, presenting symptoms and signs, imaging modalities used, histologic and immunohistochemical results, surgical data, and clinical outcomes.

RESULTS

The sample consisted of 5 males and 5 females with a mean age of 42.8 years. The course of disease ranged from 0.5 to 144.0 months with a mean time of 64.9 months. The mean size of the masses was 1.7 × 1.5 cm (range 1.0 × 0.8 cm to 2.5 × 2.5 cm). Investigations included Doppler ultrasonography (US) and computed tomography (CT) scanning. Surgical excision using various surgical approaches was performed in all patients. Postoperative pathologic examination confirmed the diagnosis of VM. The mean follow-up period was 41.2 months (range 2 months to 94 months) with no recurrence reported.

CONCLUSIONS

For solitary VM in the midcheek region, investigations, such as Doppler US or CT scanning or the use of fine-needle aspiration cytology, may aid in clinical diagnosis. The primary treatment of these lesions is surgical excision, and in our sample, the prognosis of such treatment was good with no recurrence reported.