Extracranial Head and Neck Schwannomas: Our Experience

The Rare Large Common Peroneal Nerve's Schwannoma-A Case Report and Literature Review

Schwannoma in the popliteal fossa is still rare, often diagnosed late because it grows slowly and has no symptoms. It is often misdiagnosed with connective tissue tumors or with neurological disorders originating in the spine or disorders of the peroneal nerve. Schwannoma within the common peroneal nerve is still rare in the popliteal fossa, with most tumor sizes around 2 cm in diameter due to their smaller size of nerve but can cause neurologic disturbance, especially when it is large. And over a long time, it can cause serious complaints like neurological deficits and make surgery difficult by leaving greater sequelae. There is no data yet showing the incidence of schwannoma in the common peroneal nerve. In this case, a 36-year-old woman, for 5 years, feels soreness in the popliteal fossa and pain in the right instep, suspected that a nerve was pinched, due to an abnormality in the spine. As time went on, there was a lump in the fold of the right knee, suspected to be a Baker's cyst. As time went by, the complaint was burning pain in the right instep to the lateral ankle and distal right lower leg, disturbing sleep. Tinel's sign was positive. The right instep has hypoesthesia and a slight drop in the foot. On radiological examination of the right knee, a circumferential mass appeared, measuring 5 cm × 4 cm. The diagnosis is suspicious for a common peroneal nerve tumor. The encapsulated operation to remove the tumor was carried out with a size measuring 5 cm × 4.5 cm × 4 cm. The histopathological examination showed schwannoma. After surgery, the pain disappeared, hypoesthesia and a slight drop in the foot underwent physiotherapy, and stimulation with the result gradually improved. A thorough early examination includes correct and systematic anamnesis, physical examination, and neurological evaluation such as paraesthesia, hypoesthesia, and Tinel's sign; also, additional examinations, such as radiographic, ultrasound, and MRI, are needed for early detection of schwannoma so that delays in diagnosis and surgery can be avoided to prevent neurological deficits.

Extracranial Hypoglossal Schwannoma: Case Report and Literature Review

BACKGROUND

Schwannomas are solitary neurogenic tumors originating from the myelin sheath of peripheral nerves. Extracranial hypoglossal schwannomas comprise <5% of all head and neck schwannomas and can mimic submandibular salivary gland tumors.

CASE REPORT

We report the diagnostic imaging, surgical treatment, and histopathological findings of a rare case of extracranial schwannoma of the hypoglossal nerve in a 73-year-old female, presented with an asymptomatic swelling in the left submandibular region that had been persisted for approximately three years.

CONCLUSION

Accurate diagnosis of this rare clinical entity requires comprehensive diagnostics. The optimal therapeutic strategy is nerve-sparing surgical excision, although it can be challenging.

A Rare Case of Sudden Massive Neck Tumor

A 23-year-old male patient sought evaluation at the vascular thyroid surgery clinic for a large neck tumor that appeared abruptly 10 days prior. What is your diagnosis?

Functional outcome following intracapsular resection of head and neck peripheral nerve sheath tumors: a retrospective cohort

BACKGROUND

Intracapsular resection of head and neck peripheral nerve sheath tumors (PNST) has emerged as a nerve-preserving technique compared to en bloc resection. The aim of this study was to evaluate and compare the functional outcome of both surgical techniques performed at a single tertiary referral center.

METHODS

This is a retrospective cohort of patients with head and neck PNST undergoing surgical resection from 2011 to 2021 at the Tel Aviv Sourasky Medical Center. Demographic data, the nerve of origin and surgical technique, including the use of intraoperative nerve monitoring were recorded and analyzed in association with postoperative functional outcomes.

RESULTS

Overall, 25 patients who had a cervical or parapharyngeal PNST resected were included. Nerve function was preserved in 11 of 18 patients (61%) who underwent intracapsular resection, while all those who underwent en bloc resections inevitably suffered from neurologic deficits (100%, N = 7). Sympathetic chain origin and an apparent neurologic deficit pre-operatively were associated with postoperative neural compromise.

CONCLUSION

Improved functional outcome can be anticipated following intracapsular resection of extracranial head and neck PNST compared to complete resection, particularly in asymptomatic patients.

Quantification of vessel separation using the carotid-jugular angle to predict the nerve origin of neck peripheral nerve sheath tumours: a pooled analysis of cases from the literature and a single-center cohort

BACKGROUND

Postoperative nerve palsy is a major complication following resection of neck peripheral nerve sheath tumours (PNSTs). Accurate preoperative identification of the nerve origin (NO) can improve surgical outcomes and patient counselling.

MATERIAL AND METHODS

This study was a retrospective cohort and quantitative analysis of the literature. The authors introduced a parameter, the carotid-jugular angle (CJA), to differentiate the NO. A literature review of neck PNST cases from 2010 to 2022 was conducted. The CJA was measured from eligible imaging data, and quantitative analysis was performed to evaluate the ability of the CJA to predict the NO. External validation was performed using a single-centre cohort from 2008 to 2021.

RESULTS

In total, 17 patients from our single-centre cohort and 88 patients from the literature were analyzed. Among them, 53, 45, and 7 patients had sympathetic, vagus, and cervical nerve PNSTs, respectively. Vagus nerve tumours had the largest CJA, followed by sympathetic tumours, whereas cervical nerve tumours had the smallest CJA ( P <0.001). Multivariate logistic regression identified a larger CJA as a predictor of vagus NO ( P <0.001), and receiver operating characteristic (ROC) analysis showed an area under the curve (AUC) of 0.907 (0.831-0.951) for the CJA to predict vagus NO ( P <0.001). External validation showed an AUC of 0.928 (0.727-0.988) ( P <0.001). Compared with the AUC of the previously proposed qualitative method (AUC=0.764, 0.673-0.839), that of the CJA was greater ( P =0.011). The cut-off value identified to predict vagus NO was greater than or equal to 100°. Receiver operating characteristic analysis showed an AUC of 0.909 (0.837-0.956) for the CJA to predict cervical NO ( P <0.001), with a cut-off value less than 38.5°.

CONCLUSIONS

A CJA greater than or equal to 100° predicted a vagus NO and a CJA less than 100° predicted a non-vagus NO. Moreover, a CJA less than 38.5 was associated with an increased likelihood of cervical NO.

Diagnostic and Therapeutic Strategy for Vagal Schwannoma: Case Series and Literature Review

Background and Objectives: Clinical management of vagal schwannoma is a real diagnostic and therapeutic challenge because the medical history and clinical examination are often non-specific and vagal nerve injury following surgical resection still represents an unsolved problem. The aim of this paper is to provide a case series along with a diagnostic and therapeutic algorithm for vagal schwannoma of the head and neck, combining our experience with clinical evidence available in the literature. Materials and Methods: We retrospectively analyzed a series of patients affected by vagal schwannoma who were treated between 2000 and 2020. In addition, a review of the literature on vagal schwannoma management was conducted. Based on the cases described and the literature review, we made a diagnostic and therapeutic algorithm for the management of vagal schwannoma. Results: We were able to identify 10 patients affected by vagal schwannoma and treated between 2000 and 2020. All patients presented with a painless, mobile, slow-growing lateral neck mass with onset varying from a few months to years. The preoperative diagnostic workup included ultrasound (US) in nine cases, computed tomography (CT) with contrast in six patients and magnetic resonance imaging (MRI) of the neck in seven cases. All patients included in this study were surgically treated. Conclusions: Vagal schwannoma management represents a true challenge for clinicians and surgery is currently the most effective therapeutic strategy. A multidisciplinary approach through the collaboration of otolaryngologist with other specialists is desirable to develop a tailored treatment plan for the patient.

Sinonasal and Infratemporal Schwannoma: Rare Case Report with Literature Review

Schwann cells are responsible for the production of the myelin sheath around the axons of the peripheral nervous system. Benign neoplasms which originate from Schwann cells are hence termed Schwannomas or Neurilemmomas. They present as slow-growing, solitary, encapsulated, benign masses usually in association with nerve trunks. Schwannomas are relatively rare tumors with 25-45% occurring in the head and neck region. These case reports aim to describe the presentations, work-up, and treatment of two patients with head and neck schwannoma in atypical locations. Both patients had a history of gradually increasing swelling, the first originating from the sino-nasal region and the second from the temporal/ infratemporal region. Complete surgical excision of the tumor was done in both cases with no reported recurrence at 18 months follow-up. The final diagnosis was made based on histopathology and immunohistochemistry findings. Schwannomas often present a diagnostic dilemma and should be considered a possibility in all head and neck tumors. Recurrence is rare.

A Rare Case of Cervical Vagal Nerve Schwannoma in a 30-Year-Old Ethiopian Man

Schwannoma is a slowly growing benign tumor that arises from Schwann cells. Schwannomas affect both genders equally. It occurs in any age group, but most cases are seen between the third and fifth decade. About one-fourth to one-third of extracranial schwannomas cases originate in the head and neck region. The vagus nerve, followed by the cervical sympathetic chain, is the leading site of origin in the neck region. The majority of patients with schwannomas are asymptomatic. Patients with vagal nerve schwannomas in the neck primarily present with hoarseness of voice due to paralysis of the vocal cords. Because of their rarity and the lack of a neurologic deficit as a presenting symptom, preoperative consideration of schwannomas is tough, and several differential diagnoses may be entertained.The mainstay of treatment for vagal nerve schwannoma is complete surgical excision. Here we present a rare case of cervical vagal nerve schwannoma in a 30-year-old male farmer from Ethiopia. The patient presented with a gradually increasing neck swelling of 10 years duration. He started to have hoarseness in his voice five months prior to his presentation. On examination, he had a huge anterior neck swelling. He had two FNAC results, which were inconclusive, and a neck CT. With the consideration of multinodular goiter versus spindle cell neoplasm, the neck was explored, and complete excision of the mass was done. The excisional biopsy turned out to be a classical cervical schwannoma. So this report aims to make physicians aware of the rare case of schwannomas, particularly vagal nerve schwannomas. Clinicians should consider schwannomas in the differential diagnosis of a patient presenting with a cervical mass. Furthermore, they need to be well aware of the diagnostic workup, mainly the imaging modalities, which are essential for proper preoperative planning, surgical treatment, and postoperative complications of cervical schwannomas.

Abdominal Schwannoma Mimicking Lymph Node Metastasis in Rectal Cancer

Schwannomas are rare benign tumors that are often asymptomatic and identified incidentally on imaging studies undertaken for another purpose. Schwannomas arising from the vestibular nerve are the most common site of identification; however, schwannomas can arise extracranially in any peripheral nerve tissue. Here, we present a case study of a patient with a localized rectal adenocarcinoma who was found to have a retroperitoneal schwannoma initially felt to be a lymph node metastasis of his rectal cancer. The diagnosis of schwannoma was confirmed via biopsy, which resulted in changes to the patient's overall management including radiotherapy volumes and recommendation against neoadjuvant or adjuvant systemic therapy.

Extracranial non-vestibular head and neck schwannomas: a case series with the review of literature

INTRODUCTION

Schwannomas are tumous that arise from Schwann cells. Schwannoma is one of the differential diagnosis for lateral neck swelling.

OBJECTIVE

In this study, we aim to describe the incidence, presenting clinical features and management of extracranial, non-vestibular schwannomas of head and neck region, along with the review of the literature.

METHODS

Patients treated at our tertiary care hospital for head and neck schwannomas for the past 15 years were included in the study. A review of literature on the extracranial head and neck schwannoma was also done.

RESULTS

Twenty-five cases were assessed in this study. Nineteen cases presented as a neck swelling during the initial evaluation. Vagus nerve was the most common nerve of origin, followed by the cervical sympathetic plexus. A rare presentation arising from brachial plexus C5 nerve root was also encountered. A few rare cases of schwannomas arose from the nasal cavity, paranasal sinuses, and oral cavity. Surgical excision was done in all the cases with histopathology suggestive of schwannoma. The nerve of origin of the tumor was identified in nineteen patients. Among them, 11 (58%) were from the vagus nerve, 7 (37%) from the cervical sympathetic chain, and 1 (4%) from the brachial plexus C5 nerve root.

CONCLUSION

A long-standing unilateral neck mass is the most common presenting complaint in head and neck schwannoma. The diagnosis is mainly based on clinical features and investigations such as imaging. The mainstay of treatment is complete surgical excision. The diagnosis is confirmed on the histopathological study after excision of the lesion. Due to the proximity of the tumor with the involved nerve, palsy may occur. Hence, an accurate preoperative diagnosis of schwannoma is essential.

Diagnosis and management of hypoglossal nerve-derived schwannoma in the floor of mouth: a case series

BACKGROUND

Schwannomas or neurilemmomas are well-encapsulated, benign, solitary, and slow-growing tumors that originate from Schwann cells of the nerve sheath. Extracranial schwannoma is reported to have a relatively high incidence in the tongue while an extremely low incidence in the floor of mouth. In the current study, we presented the first case series of hypoglossal nerve-derived schwannoma in the floor of mouth in Asia.

METHODS

A retrospective study of 9 surgical cases of hypoglossal nerve-derived schwannoma in the floor of mouth was performed. The patient and tumor characteristics were evaluated by physical, radiological and pathological examination. Details of operation and complications were also recorded.

RESULTS

Hypoglossal nerve-derived schwannoma in the floor of mouth showed a well-defined boundary with a firm texture, smooth surface and good mobility on palpation. The median maximum diameter of the tumors was 4.3 cm (range 2.8-7.0 cm). The median operative time and bleeding volumes were 89.4 min (range 47-180 min) and 99.2 mL (range 15-200 mL), respectively. All cases received complete surgical excision.

CONCLUSION

In this study, we presented the diagnosis and management of hypoglossal nerve-derived schwannoma in the floor of mouth for the first time in Asia. The study provided us with a recommendation for consideration of the diagnosis of hypoglossal schwannoma when a patient presents with a mass in the floor of mouth.

OUP accepted manuscript

Schwannoma arising from vagal nerve is a rare tumour. It is a slow-growing, benign mass, but rarely it might undergo malignant transformation. We report a case of a 55-year-old woman with asymptomatic Xth cranial nerve schwannoma in the left side of the neck. Initially, during the ultrasound examination, the tumour was misconceived to be a malignant lymph node. The patient underwent complete surgical excision of it. Histopathological examination revealed typical features of schwannoma. Clinical diagnose of cervical vagal nerve schwannoma is difficult. Magnetic resonance imaging is as an accurate diagnostic tool for these tumours. Surgical excision is the treatment of choice.

Management of benign nerve sheath tumors of the brachial plexus: relevant diagnostic and surgical features. About a series of 17 patients (19 tumors) and review of the literature

Brachial plexus (BP) tumors are rare, potentially difficult-to-manage lesions. The method is retrospective chart analysis. Among the 17 patients, four had neurofibromatosis and one schwannomatosis (NF +). The latter has bilateral BP tumors that remain stable on MRI at a 6.5 year follow-up. Another NF + patient has bilateral non-operable BP plexiform neurofibromas. The complaints of the 15 operated patients were radiated pain, a mass, local pain, paresthesia, a neurological deficit (n = 15, 12, 7, 10, 7). On MRI, the tumors appeared as nodular or ovoid large masses. Four operated tumors were proximal, reaching the foramen. The FDG-PET scan (n = 4) always showed tumor hypermetabolism. A preoperative percutaneous biopsy was done in three patients before neurosurgical consultation; one of them developed neurogenic pain and a sensory deficit following two percutaneous biopsies for a misinterpreted cervical lymphadenopathy. Surgery was performed using a supra-, infra-, supra- + infra-clavicular or posterior subscapular approach (n = 8, 3, 3, 1). Intraoperative electrophysiology was used in all patients. Complete or gross total resection was achieved in 14 patients. Two patients had fascicle reconstruction with grafts. Pathology revealed 13 schwannomas and two neurofibromas. Neurogenic pain transiently developed or worsened after surgery in five patients. At last follow-up, a mild deficit remained in four patients (preexisting in three). No recurrence had occurred. We conclude that a thorough examination of any patient with a cervical or axillary mass is crucial to avoid misinterpretation as a lymphadenopathy. MRI is the best imaging modality. Most BP benign tumors can be completely and safely resected through the use of microsurgical techniques and intraoperative electrophysiology.

Tibial Nerve Schwannoma: An Unexplained Cause of Lateral Foot Pain - A Rare Case Report and Review

Introduction:

Schwannoma is a benign tumor that arises from the peripheral nerve sheath. It presents as a discrete, often tender, and palpable nodule associated with neurogenic pain or paresthesia when compressed or traumatized. The growth rate is usually slow, and these lesions seldom exceed 2 cm in diameter.

Case Report:

We report the case of a schwannoma arising from the tibial nerve located in the left popliteal fossa. The patient presented with the left foot pain in the lateral plantar region without any motor deficit. The pre-operative diagnosis was made with magnetic resonance imaging (MRI) scan. He was subjected for neurolysis and excision biopsy of the lesion. The surgical specimen consisted of encapsulated white-yellow mass with irregular contours, measuring 2 × 3 cm. The cut section revealed cystic degenerations with areas of hemorrhage and necrosis. The patient reported symptom free in the post-operative period and during follow-up. Marginal excision appears to be recommended therapy for this tumorous lesion, without any evidence of recurrence during follow-up.

Conclusion:

A benign nerve sheath tumor of a peripheral nerve could be a possibility for long-standing neuropathic pain in the foot, ankle, and leg, wherein all other possibilities have been ruled out. The meticulous examination of the entire length of the tibial nerve including sciatic nerve by palpation and percussion was helpful in diagnosis which should be confirmed by MRI scan. The excision biopsy remains the gold standard treatment of choice for schwannoma of the peripheral nerve.

Feasibility of Brachial Plexus Schwannoma Enucleation With Intraoperative Neuromonitoring

Objectives

To evaluate the feasibility of brachial plexus schwannoma enucleation under intraoperative neuromonitoring.

Methods

Five patients who were treated for brachial plexus schwannoma under intraoperative neuromonitoring from 2008 to 2018 were included in this retrospective review. Neuromonitoring was performed with a 100-μV event threshold of the neuromonitoring system (NIM-2 or 3) at the deltoid, biceps brachii, triceps brachii, and brachioradialis muscles. Patient characteristics, tumor size and location, intraoperative neuromonitoring findings, and postoperative function were evaluated.

Results

The intraoperative neuromonitoring findings were in accordance with the preoperative assessment of the included nerve root. Three patients had no postoperative morbidity, one patient had temporary paresthesia of the forearm for 2 months, and one patient mild loss of grip strength for 1 month.

Conclusion

Intraoperative neuromonitoring of the arm and forearm muscles during enucleation of brachial plexus schwannoma promoted confident and successful surgery with minimal postoperative morbidity.

Schwannoma of the extracranial portion of the accessory nerve presenting as spinal adenopathy

Schwannomas are benign tumours arising from Schwann cells in the peripheral nerve. The schwannoma of the accessory nerve is a very rare entity. We report a case of Schwannoma of the extracranial accessory nerve. A 22-year-old man presented with a slow-growing mass, located on the right upper neck. The patient did not have any neurological deficit. CT scan showed a hypodense mass behind sternocleidomastoid muscle. The suspected diagnosis was an adenopathy of the accessory spinal chain. Surgery was done via transcervical approach. The histopathological analysis concluded with a diagnosis of schwannoma. No recurrence was noted at the follow-up examination 29 months after surgery.