Extracranial head and neck schwannomas: a study of the nerve of origin

Introduction. Schwannomas are tumors of neurogenic origin, that arise from Schwann cells which surround peripheral, cranial and autonomic nerves. Schwannomas account for only 5% of all benign soft tissue tumors, and 25-45% of extracranial schwannomas are present in the head and neck region. They are usually classified according to the nerve of origin and the site within the head and neck. Case report. We presented extremely rare extracranial localizations of schwannomas and discussed about diagnosis and management of these tumors. Conclusion. Schwannomas are slow-growing tumors and late symptoms appearance may cause a delay in diagnosis and treatment of patients with these tumors. An appropriate diagnostic protocol is indispensable tool in performing a differential diagnosis of malignant from benign lesions. Choice of surgical approach depends on schwannomas localization.

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Schwannomas of ear, nose, throat and neck

Surgical Techniques Development ◽

10.4081/std.2019.7550 ◽

2019 ◽

Vol 9 (1) ◽

Author(s):

Nilam U. Sathe ◽

Sheetal Shelke ◽

Ankur Pareek ◽

Kamini Chavan

Keyword(s):

Head And Neck ◽

Management Strategy ◽

Cranial Nerves ◽

Needle Aspiration ◽

Aspiration Cytology ◽

Neck Masses ◽

Needle Aspiration Cytology ◽

Nerve Of Origin ◽

Tomography Scan ◽

Nose And Throat

Schwannoma is a benign tumour of nerve sheath origin with latent malignant potential. All cranial nerves can give rise to schwannoma except for olfactory and optic nerves, which are devoid of Schwann cell. Schwanommas are usually asymptomatic and present late owing to compression of nerve of origin. We present our study of 19 cases of schwannoma arising from unusual sites in head and neck, having varied presentation and the challenges faced in management of these cases. These cases presented in detail to the department of Ear, Nose and Throat, KEM Hospital, and were thoroughly evaluated clinically and radiologically to formulate a management strategy. Schwannoma of the head and neck is a rare entity but should be considered as differential diagnosis in unilateral nasal mass cases, palatal masses, anterior and lateral neck masses. Nerve of origin may not always be clear preoperatively but the possibility of postoperative loss of nerve function should be kept in mind. Radiological investigations like computed tomography scan and magnetic resonance imaging play a pivotal role in management. In case of nonvascular neck tumours, fine needle aspiration cytology is crucial but has low accuracy in the diagnosis of neural tumors. Histopathology of excised tumour remains the gold standard in diagnosis.

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Head and Neck Schwannomas: A Surgical Challenge—A Series of 5 Cases

Case Reports in Otolaryngology ◽

10.1155/2018/4074905 ◽

2018 ◽

Vol 2018 ◽

pp. 1-10 ◽

Cited By ~ 1

Author(s):

Ishtyaque Ansari ◽

Ashfaque Ansari ◽

Arjun Antony Graison ◽

Anuradha J. Patil ◽

Hitendra Joshi

Keyword(s):

Brachial Plexus ◽

Head And Neck ◽

Case Series ◽

Neck Region ◽

Anatomical Location ◽

Diagnostic Dilemma ◽

Neurogenic Tumors ◽

Peripheral Nerve Sheath Tumors ◽

Formidable Challenge ◽

Nerve Of Origin

Background. Schwannomas, also known as neurilemmomas, are benign peripheral nerve sheath tumors. They originate from any nerve covered with schwann cell sheath. Schwannomas constitute 25–45% of tumors of the head and neck. About 4% of head and neck schwannomas present as a sinonasal schwannoma. Brachial plexus schwannoma constitute only about 5% of schwannomas. Cervical vagal schwannomas constitute about 2–5% of neurogenic tumors. Methods. We present a case series of 5 patients of schwannomas, one arising from the maxillary branch of trigeminal nerve in the maxillary sinus, second arising from the brachial plexus, third arising from the cervical vagus, and two arising from cervical spinal nerves. Result. Complete extracapsular excision of the tumors was achieved by microneurosurgical technique with preservation of nerve of origin in all except one. Conclusion. Head and neck schwannoma though rare should be considered as a differential diagnosis of a unilateral slow growing mass in the head and neck region, particularly in an adult. Schwannomas are always a diagnostic dilemma as they are asymptomatic for long time, and histopathology is the gold standard for diagnosis. As a rule, treatment is surgical and dictated by the location of the tumor and nerve of origin. Due to its rarity, complex anatomical location and morbidity risk postexcision, they can pose a formidable challenge to surgeons. This study aims to describe the presentation, workup, surgical technique, and outcome.

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A novel technique to identify the nerve of origin in head and neck schwannomas

The Journal of Laryngology & Otology ◽

10.1017/s0022215118000567 ◽

2018 ◽

Vol 132 (5) ◽

pp. 452-456 ◽

Cited By ~ 2

Author(s):

H H Ching ◽

A G Spinner ◽

N H Reeve ◽

R C Wang

Keyword(s):

Head And Neck ◽

Neurological Deficits ◽

Diagnostic Challenge ◽

Accurate Identification ◽

Patient Counselling ◽

Maxillary Nerve ◽

Lidocaine Injection ◽

Operative Planning ◽

The Masses ◽

Nerve Of Origin

AbstractObjective:Identifying the nerve of origin in head and neck schwannomas is a diagnostic challenge. Surgical management leads to a risk of permanent deficit. Accurate identification of the nerve would improve operative planning and patient counselling.Methods:Three patients with head and neck schwannomas underwent a diagnostic procedure hypothesised to identify the nerve of origin. The masses were infiltrated with 1 per cent lidocaine solution, and the patients were observed for neurological deficits.Results:All three patients experienced temporary loss of nerve function after lidocaine injection. Facial nerve palsy, voice changes with documented unilateral same-side vocal fold paralysis, and numbness in the distribution of the maxillary nerve (V2), respectively, led to a likely identification of the nerve of origin.Conclusion:Injection of lidocaine into a schwannoma is a safe, in-office procedure that produces a temporary nerve deficit, which may enable accurate identification of the nerve of origin of a schwannoma. Identifying the nerve of origin enhances operative planning and patient counselling.

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Implications for clinical staging of metastatic cutaneous squamous carcinoma of the head and neck based on a multicenter study of treatment outcomes

The Journal of Laryngology & Otology ◽

10.1017/s0022215106002891 ◽

2005 ◽

pp. 1

Keyword(s):

Head And Neck ◽

Treatment Outcomes ◽

Multicenter Study ◽

Squamous Carcinoma ◽

Clinical Staging

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[Triple-combined therapy of malignant cancer of the head and neck-maxillary cancer]

Journal of Dental Education ◽

10.1002/j.0022-0337.1969.33.4.tb00237.x ◽

1969 ◽

Vol 33 (4) ◽

pp. 596-598

Author(s):

Y Sato

Keyword(s):

Head And Neck ◽

Combined Therapy ◽

Maxillary Cancer

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Copper-dependent ATP7B up-regulation drives the resistance of TMEM16A-overexpressing head-and-neck cancer models to platinum toxicity

Biochemical Journal ◽

10.1042/bcj20190591 ◽

2019 ◽

Vol 476 (24) ◽

pp. 3705-3719 ◽

Cited By ~ 2

Author(s):

Avani Vyas ◽

Umamaheswar Duvvuri ◽

Kirill Kiselyov

Keyword(s):

Oxidative Stress ◽

Head And Neck ◽

Transcriptional Activation ◽

Platinum Resistance ◽

Mrna Levels ◽

Strong Positive Correlation ◽

Platinum Compounds ◽

Copper Chelation ◽

Novel Approach ◽

Cancer Models

Platinum-containing drugs such as cisplatin and carboplatin are routinely used for the treatment of many solid tumors including squamous cell carcinoma of the head and neck (SCCHN). However, SCCHN resistance to platinum compounds is well documented. The resistance to platinum has been linked to the activity of divalent transporter ATP7B, which pumps platinum from the cytoplasm into lysosomes, decreasing its concentration in the cytoplasm. Several cancer models show increased expression of ATP7B; however, the reason for such an increase is not known. Here we show a strong positive correlation between mRNA levels of TMEM16A and ATP7B in human SCCHN tumors. TMEM16A overexpression and depletion in SCCHN cell lines caused parallel changes in the ATP7B mRNA levels. The ATP7B increase in TMEM16A-overexpressing cells was reversed by suppression of NADPH oxidase 2 (NOX2), by the antioxidant N-Acetyl-Cysteine (NAC) and by copper chelation using cuprizone and bathocuproine sulphonate (BCS). Pretreatment with either chelator significantly increased cisplatin's sensitivity, particularly in the context of TMEM16A overexpression. We propose that increased oxidative stress in TMEM16A-overexpressing cells liberates the chelated copper in the cytoplasm, leading to the transcriptional activation of ATP7B expression. This, in turn, decreases the efficacy of platinum compounds by promoting their vesicular sequestration. We think that such a new explanation of the mechanism of SCCHN tumors’ platinum resistance identifies novel approach to treating these tumors.

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