Schwannoma of the Sinonasal Tract and the Pterygopalatine Fossa with or without Intracranial Extension

Nasal Cavity Schwannoma-A Case Report and Review of the Literature

Schwannomas are rare slow-growing benign tumors arising from Schwann cells lining the nerve sheaths. Head and neck schwannomas account for about one-third of all cases, and only 4% of them arise from the sinonasal tract. Its diagnosis is based on histology and immunohistochemistry. Complete surgical excision is the most recommended treatment option, and endoscopic surgery has been widely performed in recent years. In this study, we presented a case of a 55-year-old female with schwannoma arising from the lateral wall of the nasal cavity, causing epistaxis and rhinorrhea. The patient underwent endoscopic excision with prompt resolution of symptoms. The reported cases of nasal cavity schwannoma were reviewed and summarized for educational purposes.

Sphenoid sinus schwannoma with adhesion to the carotid canal

Few reports have been made on the presentation and treatment of schwannomas originating in the sphenoid sinus due to their rarity. We report the case of a 60-year-old woman who presented with a cyst-like mass in the right sphenoid sinus on magnetic resonance imaging. Computed tomography showed a bone defect in the internal carotid artery (ICA) and enlargement of the round foramen on the affected side. A histopathological diagnosis of schwannoma was made, and endoscopic sinus surgery was performed. The anterior part of the tumor could be easily removed by aspiration; however, its adhesion to the ICA was remarkable, and its boundaries were unclear. Although partial paralysis of the maxillary nerve remained, no recurrence occurred for over 10 years. Careful evaluation should be performed to check for bone defects in the nerve to differentially diagnose schwannoma from cystic masses of the sphenoid sinus. Additionally, excision of masses similar to the presented case may expectedly be difficult because of unclear excisional margins and strong capsule adherence to important organs such as the ICA. Moreover, correct imaging, histopathological diagnosis, and appropriate informed consent are essential before surgery.

Pterygopalatine fossa schwannoma-case report and literature review

INTRODUCTION

Schwannomas are well-differentiated, benign tumours that originate from the Schwann cells of nerve sheaths. They constitute 25-45% of all the head and neck tumours and can cause significant morbidity depending on the site of origin. The pterygopalatine fossa is the rarest site of involvement, with only a few cases reported in the literature.

CASE PRESENTATION

This is the case of a 46-year-old male who presented with a twelve [12] month history of left-sided facial pain and progressive swelling. Contrast-enhanced computed tomography (CT) and magnetic resonance imaging (MRI) revealed a large soft tissue lesion located in the left pterygopalatine fossa (PPF). Surgical management is presented, and technical details of the repair are discussed. At one year follow-up, there were no signs of recurrence, and the cosmetic outcome was satisfactory.

DISCUSSION

This case is one of a handful of reported cases of PPF schwannomas in the English literature. Although a significant percentage of schwannomas arise in the head and neck region, the pterygopalatine fossa is the rarest site of involvement. Due to its clinically inaccessible location and complex connections, the pterygopalatine fossa can act as a natural conduit for the spread of inflammatory and neoplastic diseases in the head and neck.

CONCLUSION

Currently, the endoscopic endonasal approach (EEA) is preferred due to its safety and good oncologic outcome. There is also decreased morbidity as it is minimally invasive. Furthermore, surgeons embarking on the EEA should be equipped with an image guidance system and be trained in advanced endoscopic techniques. However, the open approach remains a reliable and proven surgical method to treat large tumours located within this intricate and inaccessible area.

A novel landmark for endonasal surgery of the pterygopalatine fossa and inferior orbital fissure: The orbito-pterygo-sphenoidal ligament

The pterygopalatine fossa contains a dense and complex array of neurovascular structures vulnerable to accidental surgical injury. This study aims to describe a novel landmark, the orbito-pterygo-sphenoidal ligament (OPSL), and implications of this structure for surgery in the pterygopalatine fossa and the inferior orbital fissure. Six cadaveric specimens (12 sides) were dissected using an endonasal approach to expose the periosteal layers associated with the pterygopalatine fossa and orbit. The thickened triangular-shaped ligament at their confluence was termed the OPSL. Dimensions of its lateral, inferior, and medial borders were measured, and their anatomical relationships defined. The pterygopalatine ganglion and the maxillary nerve lie immediately inferior and deep into the OPSL. The superior aspect of the posterior nasoseptal artery and nerve are covered by the medial OPSL. The lateral and inferior borders of the OPSL are contiguous with the periorbita and the periosteum of the pterygopalatine fossa, respectively. Along the medial border of the ligament, the openings of the palatovaginal fissure, vidian canal, and foramen rotundum were sequentially identified in a medial to lateral trajectory. The length of the lateral, inferior, and medial borders of the triangular OPSL were 13.25 ± 0.62, 14.25 ± 0.45, and 12.08 ± 0.90 mm, respectively. The OPSL is a thick, triangular-shaped fascial confluence, which may serve as a landmark for procedures within the pterygopalatine fossa and the inferior orbital fissure.

Schwannoma of the sinonasal tract: case report with review of the literature

Schwannomas of the sinonasal tract are rare, accounting for <4% of head and neck schwannomas. We report the case of a 61-year-old male who presented with unilateral nasal symptoms. Examination and imaging revealed a unilateral polyp at the level of the middle turbinate, with an initial biopsy suggestive of an inflammatory polyp. Due to the persistence of the patient's symptoms and his polyp despite medical therapy, endoscopic nasal polypectomy was performed. The histology surprisingly showed a schwannoma. No further interventions were carried out, and the patient remains disease-free 6 months postoperatively. A review of the literature comprising 60 cases is included. An optimal clinical approach to the investigation and management of schwannomas of the sinonasal tract is subsequently discussed.

Neurilemmoma of the Nasal Cavity and Paranasal Sinuses

OBJECTIVES

Neurilemmoma in the nasal cavity and paranasal sinuses is very rare. The study aimed to improve the understanding of neurilemmoma in the nasal cavity and paranasal sinuses.

MATERIALS AND METHODS

The clinical data of 10 patients with neurilemmoma in the nasal cavity and paranasal sinuses treated from January 2014 to June 2019 in our hospital were retrospectively studied.

RESULTS

There were 6 females and 4 males patients in our study. The mean age was 49.5 years (range 37-77 years), and the most common clinical symptom was unilateral nasal obstruction. The site of tumor included the nasal cavity, maxillary sinus, ethmoid sinus, and sphenoid sinus. There were 2 cases with malignant neurilemmoma. Nine patients underwent functional endoscopic sinus surgery (FESS); however, 1 patient underwent FESS combined with the lateral rhinotomy for complete resection of the tumor. Two patients with malignant neurilemmoma received postoperative radiotherapy. The mean follow-up was 3.82 years (range 2-7 years). There were no incidences of tumor recurrence during the study period.

CONCLUSIONS

Neurilemmoma in the nasal cavity and paranasal sinuses is a mainly benign tumor. Complete surgical excision by FESS is the only treatment option for neurilemmoma in the nasal cavity and paranasal sinuses; while malignant neurilemmoma needs postoperative radiotherapy.

Role of endoscopic surgery in the management of sinonasal and skull base schwannomas

BACKGROUND

The purpose of this study was to report our experience with the endoscopic management of sinonasal schwannomas, analyzing the advantages, limitations, and outcomes of the technique.

METHODS

A retrospective analysis was carried out on 11 patients treated endoscopically between 2000 and 2014 at a single institution.

RESULTS

Eight patients underwent an exclusive endoscopic endonasal approach, whereas, in 3 patients, an osteoplastic flap was combined because of massive or lateral frontal sinus involvement. The tumor extended into the orbit in 5 cases, and involved the skull base in 5 patients who required a concomitant endoscopic duraplasty. No evidence of disease was observed in 10 patients after a mean follow-up of 90.1 months (range, 14-189 months). One patient was alive with persistence of disease, although asymptomatic.

CONCLUSION

The endoscopic endonasal approach is a valid alternative for the vast majority of sinonasal schwannomas with minimal morbidity for the patient. © 2016 Wiley Periodicals, Inc. Head Neck 38: E2074-E2082, 2016.