Intrathoracic vagus nerve tumours

Neurofibromas of the Phrenic Nerve: A Case Report and Review of the Literature

BACKGROUND

Phrenic neurofibromas are a rare pathologic entity, with 9 cases described in the English literature. They may occur in conjunction with or independently of neurofibromatosis type 1. Phrenic neurofibromas pose distinct therapeutic challenges compared with the more common phrenic schwannoma. We describe here a 12-year-old boy with neurofibroma of the left phrenic nerve presenting as dextroposition of the heart after paralysis of the left hemidiaphragm allowed herniation of abdominal contents into the left hemithorax and displaced the heart.

METHOD

Surgical resection of the tumor followed by diaphragmatic plication was performed to assess its degree of malignancy, reduce abdominal herniation, and improve lung capacity.

RESULTS

The operation markedly improved his hemidiaphragmatic elevation.

CONCLUSIONS

The spectrum of management options ranges from conservative surveillance to open thoracic surgery. Functional preservation of the phrenic nerve is technically challenging, and although phrenic neurofibromas often present with absent function that cannot be recovered, surgical intervention can be fruitful in restoring lung capacity through diaphragmatic reconstruction.

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.

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.

CT evaluation of vocal cord paralysis due to thoracic diseases: a 10-year retrospective study

PURPOSE

To discuss computed tomography (CT) evaluation of the etiology of vocal cord paralysis (VCP) due to thoracic diseases.

MATERIALS AND METHODS

From records from the past 10 years at our hospital, we retrospectively reviewed 115 cases of VCP that were evaluated with CT. Of these 115 cases, 36 patients (23 M, 13 F) had VCP due to a condition within the thoracic cavity. From these cases, we collected the following information: sex, age distribution, side of paralysis, symptom onset date, date of diagnosis, imaging, and primary disease. The etiology of VCP was determined using both historical information and diagnostic imaging. Imaging procedures included chest radiograph, CT of neck or chest, and esophagography or esophagoscopy.

RESULTS

Thirty-three of the 36 patients with thoracic disease had unilateral VCP (21 left, 12 right). Of the primary thoracic diseases, malignancy was the most common (19, 52.8%), with 18 of the 19 malignancies presenting with unilateral VCP. The detected malignant tumors in the chest consisted of thirteen lung cancers, three esophageal cancers, two metastatic tumors, and one mediastinal tumor. We also found other underlying etiologies of VCP, including one aortic arch aneurysm, five iatrogenic, six tuberculosis, one neurofibromatosis, three benign nodes, and one lung collapse. A chest radiograph failed to detect eight of the 19 primary malignancies detected on the CT. Nine patients with lung cancer developed VCP between follow-ups and four of them were diagnosed with a progression of malignancy upon CT evaluation of VCP.

CONCLUSION

CT is helpful for the early detection of primary malignancy or progression of malignancy between follow-ups. Moreover, it can reveal various non-malignant causes of VCP.

[Neurogenic tumors of the mediastinum in adults]

In adults, mediastinal neurogenic tumours constitute the third group of mediastinal tumours, after thymomas and lymphomas. If the group of neurogenic tumour is frequent, each type of tumour is relatively unusual in everyday's clinic. Among them, nerve sheath tumours are the more frequent, followed by tumour of the autonomic system. Askin tumour remains uncommon. Treatment of this tumour requires complete preoperative work-up, including standard radiography, CT-scan, MRI, and sometimes nuclear imaging. In most cases, the treatment is based on surgical resection, and may be associated with radiotherapy or chemotherapy in case of malignant tumour or incomplete resection. Better understanding of these tumours, including their molecular abnormalities, may lead to new changes in their classifications, and to their management.

[Intrathoracic vagal nerve schwannoma preoperative diagnosis is correct because of clinical and characteristic CT findings--a case report and review of the literature]

A 60-year-old man was operated with the clinical diagnosis of intrathoracic vagal nerve schwannoma because of characteristic CT findings and no symptom of neurofibromatosis. Thoracoscopic surgery was performed and it was confirmed pathologically. Intrathoracic vagal nerve tumor is rare, so preoperative diagnosis seems to be difficult. We review the intrathoracic vagal nerve tumors reported in Japan (52 cases of schwannoma and 9 cases of neurofibroma), and analyzed the tumor location, furthermore, the relationship of neurofibromatosis and schwannoma and neurofibroma on vagal nerve tumor.

[Schwannoma of the intrathoracic vagus nerve]

Schwannomas, or neurilemomas, are tumors that originate in the sheaths covering peripheral nerve fibers. They are usually encapsulated, slow growing, and asymptomatic. Such tumors may appear in any nerve, although most are found in the extremities. Intrathoracic vagus schwannomas are very rare and only 72 cases have been reported. We present a new case in a 39-year-old man in whom chest film showed a well-defined, homogeneous mass measuring 3 cm in diameter located in the left para-aortic region. The presence of a smooth tumor on the vagus nerve and recurrent loop was confirmed by left lateral thoracotomy. After removal, the tumor was shown to be a vagal nerve schwannoma.

Thoracoscopic excision of a malignant schwannoma of the intrathoracic vagus nerve

Malignant schwannomas of the intrathoracic vagus nerve are rare tumors. A patient underwent resection of a mediastinal malignant schwannoma of the vagus nerve using video-assisted thoracoscopy, with no recurrence at 18 months.

Neurogenic tumors of the mediastinum originated from the vagus nerve

Thirty-nine patients with neurogenic tumors observed between 1974 to 1992 were reviewed. There were 32 patients with neurilemoma, one with neurofibroma, five with ganglioneuroma, and one with malignant neurilemoma. Two cases of neurilemoma originated from the vagus nerve, which is very rare. Surgical resection is recommended, not only to confirm the nature of the lesion, but also to prevent further growth and compression on adjacent structures. For benign encapsulated neurogenic tumors, resection is curative.

An intrathoracic vagus nerve schwannoma invading the trachea

A patient with a schwannoma of the intrathoracic vagus nerve is presented. The tumor invaded the trachea and caused dyspnea. It was successfully excised by a segmental resection of the trachea with end-to-end anastomosis. This instance of an intrathoracic vagus tumor invading the trachea is, as far as we know, the first reported in the world.

Intrathoracic vagus nerve neurofibroma and sudden death in a patient with neurofibromatosis

A 21 year old man with type 1 neurofibromatosis was found dead in the middle of the night. Postmortem examination revealed a large neurofibroma arising from the right intrathoracic vagus nerve, which might have contributed to his sudden death.

Neurofibrosarcoma of the intrathoracic vagus nerve. Case report

A rare case of neurofibrosuarcoma of the intrathoracic vagus nerve in a man with von Recklinghausen's neurofibromatosis is reported. Magnetic resonance imaging accurately demonstrated the tumour and its relations to surgically important structures. Resection, in accordance with general recommendations for such tumours, was successfully performed.

Tumours involving the intrathoracic vagus and phrenic nerves demonstrated by computed tomography: anatomical features

Four cases of mediastinal tumours involving the intrathoracic vagus and phrenic nerves are presented and their computed tomographic (CT) features are described with particular attention to the intrathoracic course of these nerves. One case of mediastinal plexiform neurofibromatosis appeared as a series of low attenuation masses along the intrathoracic course of the nerves. Three examples of neurilemmomas of the vagus nerve appeared as masses with central low attenuation; one in the retrocaval area, one to the left of the aortic arch, and one in the right paraoesophageal area. Familiarity with the CT anatomy of the vagus and phrenic nerves will greatly assist in the diagnosis of mediastinal tumours.

Intrathoracic tumors of the vagus nerve

Two patients had resection of a middle mediastinal neurilemmoma of the vagus nerve. Twenty-seven other neurogenic tumors of the intrathoracic vagus are reviewed. These tumors are generally asymptomatic except for hoarseness in an occasional patient.

Intrathoracic tumors arising from the vagus nerve. Review of resected tumors in Japan

Nineteen surgically treated intrathoracic vagus nerve tumors (16 neurilemmomas, 3 neurofibromas), including three treated by the authors, were reviewed. Tumor resection with vagus nerve amputation was performed in 14 and intracapsular excision without nerve amputation in 3 of the 17 adequately recorded cases. The location of vagus nerve tumor was the left upper mediastinum in 11 patients, almost all of whom were hoarse postoperatively due to sacrifice of the recurrent laryngeal nerve.

Neurofibrosarcoma of the vagus nerve

A patient whose symptoms of cough and intermittent hoarseness were due to a neurofibrosarcoma of the vagus nerve is described. Attention is drawn to the rarity of the tumour and a short review of the pathology and treatment of neurofibrosarcoma is discussed.

Solitary neurofibroma of the trachea

The patient was a 60-year-old white male who, for 18 months, had complained of a substernal wheeze on exertion, exertional dyspnoea and cough, and attacks of acute respiratory distress. There was no haemoptysis or dyshpagia and he was treated for bronchial asthma until bronchoscopy revealed the tumour which had not been recognized in plain chest films. He showed no evidence of a neurofibromatosis and apart from reduction in pulmonary function tests on a PO2 of 74, his laboratory tests were negative. There was no family history of neurofibromatosis. He underwent thoracotomy and a smooth rounded pedunculated tumour, 2.5 cm in diameter, arising from the posterior wall of the trachea, 3 cm above the carina was excised. He has had no tumour recurrence.