Schwannoma of the vagus nerve, a rare middle mediastinal neurogenic tumor: case report

Retrospective analysis of the clinical presentation and imaging of eight primary benign mediastinal schwannomas

OBJECTIVE

Mediastinal schwannomas are sometimes confused with other neoplasms during initial radiological studies, especially when there is a history of cancer in another area. In these cases, a more accurate analysis using computed tomography (CT) or even magnetic resonance (MRI) is required. Our study aimed to perform a retrospective analysis of the clinical and imaging features for a series of patients with mediastinal schwannomas that were confirmed by histology and immunohistochemistry.

RESULTS

We found eight patients, five men and three women, with an average age of 51 years for this study. The main signs and symptoms at diagnosis were chest pain, dyspnea, cough, and dysphagia. CT showed that the tumor was located in the posterior compartment of the chest in 7/8 cases. Tumors > 10 cm were more heterogeneous and showed cystic changes. All patients underwent posterolateral thoracotomy, and radiological follow-up showed no evidence of recurrence. Histological analysis was considered the gold standard to confirm diagnosis, along with at least one neurogenic IHC marker. In conclusion, mediastinal schwannomas are benign encapsulated tumors. According to CT, schwannomas > 10 cm show cystic degeneration more frequently. Posterolateral thoracotomy allows complete resection and is considered the surgical approach of choice.

Giant Intrathoracic Schwannoma of the Left Vagus Nerve Manifesting as Atrial Fibrillation

Posterior mediastinal tumors are not infrequent, and among them neurogenic masses and schwannomas are the most common histologic varieties. These benign, initially asymptomatic tumors later become symptomatic as a result of mass effect. Surgical excision is the preferred therapy, and the approach can be determined according to the dimensions of the lesion. This report describes the case of a giant schwannoma originating from the left vagus nerve in a middle-aged woman whose symptoms were exertion-induced dyspnea and atrial fibrillation.

Incidental ancient schwannoma of the posterior mediastinum in a young male: a rare scenario

Ancient schwannoma is a distinctive type of schwannoma occurring mostly in the retroperitoneum. The presentation in the posterior mediastinum is rare. The term 'ancient' represents a group of neurogenic tumours showing degenerative changes with marked nuclear atypia. A 26-year-old man was incidentally detected to have an upper mediastinal mass lesion in the chest X-ray. MRI chest revealed a mixed signal intensity lesion in the left side upper para spinal region of the posterior mediastinum. The patient underwent left posterior thoracotomy and excision of the mass was done. Postoperative period was uneventful. The histopathological feature was typical of Ancient schwannoma. The patient is on regular follow-up and disease free until.

Angiographic embolization followed by piecemeal resection of giant posterior mediastinal schwannoma: Case report and concise review

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Radiographic assessment of spinal cord involvement is essential.

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Histology is necessary to establish etiology, prognosis, and treatment plan.

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Large tumors may require posterolateral thoracotomy and piecemeal resection.

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Preoperative angiography may identify arteries shared by the tumor and spinal cord.

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Preoperative angioembolization may reduce tumor vascularity and operative blood loss.

Introduction: Posterior mediastinal masses present unique diagnostic and therapeutic challenges, particularly when large highly vascularized tumors extend toward or emanate from the spinal cord. The rare nature of these tumors precludes the development of standardized management algorithms, underscoring the importance of case reports.

Presentation of case: A 57 year old female presented with exertional dyspnea and right chest pressure. Chest radiography followed by computed tomography (CT) scan demonstrated a 13 cm posterior mediastinal mass involving the T7 vertebral body. CT-guided percutaneous biopsy confirmed benign schwannoma. During open exploration, the tumor bled easily with contact. Angiography with intercostal arterial embolization decreased tumor vascularity while preserving spinal cord perfusion. Subsequent piecemeal resection facilitated exposure of the tumor base and complete resection. Postoperative recovery was uneventful.

Discussion: Neurogenic tumors are most commonly located in the posterior mediastinum. When untreated, schwannomas continue to grow, and will inevitably cause compressive symptoms if given sufficient time. Therefore, resection is recommended. This may be performed thoracoscopically in select patients with small tumors, avoiding the morbidity of a thoracotomy incision.

Conclusion: Large posterior mediastinal schwannomas require posterolateral thoracotomy and resection. Preoperative angiography helps identify arteries shared by the tumor and the spinal cord, and embolization may reduce tumor vascularity and operative blood loss thereby permitting safer resection.

Middle mediastinal schwannoma concealed by asthma and GORD

Neurogenic tumours of the mediastinum in adults occur most often at the posterior mediastinum, majority of which are benign of nerve sheath in origin. A 72-year-old woman, known asthmatic, presented with chronic symptoms of hoarseness, dysphagia, chest heaviness, easy fatigability, cough, epigastric pain, feeling of abdominal fullness and choking with food intake and at a supine position. Treated for other disorders, routine chest X-ray incidentally found a homogenous convex radiodensity at the right paratracheal area; mass which was also observed with CT and 18F-fludeoxyglucose-positron emission tomography/CT scan studies. Mediastinoscopy with biopsy showed spindle to plump cells with strong S100 positivity. Thoracoscopic surgery done to completely excise the mass found it to be benign schwannoma.

Vagus nerve schwannoma in the right upper mediastinum

A 35‐year‐old woman was admitted to our hospital with an abnormal shadow on her chest roentgenogram. Computed tomography showed that a tumor was located in the right upper mediastinum. Resection of the tumor by video‐assisted thoracoscopic surgery was performed. Operative findings determined that the tumor originated from the right vagus nerve and was diagnosed as schwannoma by pathological examination.

Thoracoscopic resection of a vagal schwannoma in the superior mediastinum: A case report

Neurogenic tumors are the most common type of mediastinal tumor and constitute the majority of neoplasms of the posterior mediastinum. Schwannomas originating from the intrathoracic vagus nerve are extremely rare. The present study describes the case of a 58-year-old man with a large vagal schwannoma in the left superior mediastinum. A large tumor with a round shape was identified in the left superior mediastinum. The tumor originated from and encased the vagus nerve. Using video-assisted thoracoscopic surgery, the tumor was completely excised with amputation of the vagus nerve encased within in the tumor. One year post-surgery, the patient was free of recurrence with no symptoms other than hoarseness.

Ancient schwannoma mimicking a thyroid mass with retrosternal extension

We report the case of a middle-aged hypothyroid woman presenting with a neck swelling, voice change and breathing difficulty. On evaluation, she was diagnosed to have goitre with retrosternal extension. The mass was surgically excised and a histopathological report of ancient schwannoma was obtained. A review of literature on schwannomas of the head and neck was carried out. An ancient schwannoma should be considered as one of the differential diagnosis of a cervical mass, even though the clinical presentation point towards a thyroid swelling. At 6 months follow-up, the patient was found to be asymptomatic except for a hoarse voice.

Giant intrathoracic left-sided vagal schwannoma

Extensive intrathoracic tumors are rarely diagnosed radiologically without pre-existing symptoms. If located in the posterior mediastinum, it is most probably a neurogenic tumor. Schwannoma is the most frequent neurogenic neoplasia in this location, and most schwannomas are benign. To specify the diagnosis, a thoracic computed tomography must be done; if the growth is close to the medullary canal, a magnetic resonance tomography of the spinal column is necessary to detect neuroforamen infiltration. Our surgical goal was complete excision of the tumor, although many authors favor a minimally invasive approach. In our patient we performed open, en bloc removal of the tumor; removal of parts of the intraforamen was also necessary, which necessitated revision of the affected neuroforamen. Histologically this was a very rare case of vagal schwannoma (which has an incidence of less than 6% of all neurogenic tumors). This patient has a very promising prognosis following complete tumor resection.

Schwannoma of the pulmonary artery

Schwannoma (neurilemmoma) originating from the pulmonary artery has not before been described. A 65 year-old male presented with dyspnoea on exertion. CT scan was negative for pulmonary thromboembolism, but showed a well circumscribed, heterogeneous mass, 52 mm × 45 mm × 41 mm, straddling the left pulmonary artery and compressing the left atrium. The mass was found at surgery to be originating from the lateral wall of the left pulmonary artery. The tumour was completely resected, and the pulmonary artery reconstructed. The mass was found to be a benign schwannoma on histopathology.