Oesophageal schwannoma

Clinical History

A 44-year-old woman, without relevant personal or familial background, presented with exertional dyspnoea and a 7-months history of progressive dysphagia. The results of the physical examination, haemogram and laboratory tests were normal.

Imaging Findings

Chest radiograph showed a mass in the middle mediastinum (Fig. 1). Computed tomography with intravenous contrast confirmed the presence of a mass with 85 mm in diameter, between the trachea and the vertebrae (Fig. 2), extending from the thoracic outlet to the carina of the trachea, ovoid-shaped, solid and homogeneous, with clear limits. It compressed the upper thoracic oesophagus and displaced it to the left, without a clear cleavage plane with the oesophageal wall; and it compressed the posterior wall of the trachea. Involvement of adjacent mediastinal structures and local regional ganglia was not observed.
Diagnostic thoracoscopy confirmed that the mass was attached to the wall of the thoracic oesophagus. Surgical resection was decided (Fig. 3), with subtotal oesophagectomy and reconstruction of the intestinal tract by retrosternal ascendant gastric plasty. The histopathological study showed that it was a schwannoma of the oesophageal wall (S100+).

Discussion

Although neurogenic tumours are the most frequent ones in the posterior mediastinum, they are very rare in the middle mediastinum. Actually, approximately 30 cases of oesophageal schwannomas have been published in the literature [1].

Most tumoural lesions of the oesophagus, between 90 and 95% of cases, are squamous cell carcinomas. Benign primary tumours of the oesophagus are uncommon. They are usually detected incidentally as a mediastinal mass in asymptomatic patients. More than 80% of benign tumours are leiomyomas, which are predominantly located in the mid and lower oesophagus, while schwannomas or tumours of the peripheral nerve sheaths are rare in gastrointestinal locations [2].

Oesophageal schwannomas are more frequent in women than in men, with a mean age of presentation around 54 years [3]. They are usually asymptomatic, although symptoms appear as they grow in size. Symptoms include dysphagia, dyspnoea, weight loss and thoracic pain [4]. The most frequent location is the upper portion of the oesophagus, in the middle mediastinum. Since this tumour is extremely rare, the final diagnosis is established through histopathological analysis after surgical resection [2, 5].
Schwannomas are composed of fusiform cells either densely packed (Antoni A pattern) or closely organized in association with a myxoid stroma (Antoni B pattern), which is more frequent in areas of infarction. Immunostaining was positive for protein S-100 and negative for smooth muscle markers.
Total resection, generally through endoscopic or thoracoscopic enucleation, is the treatment of choice in small well-delimited lesions, where the prognosis is excellent. Tumours larger than 8 cm or malignant tumours should be treated with oesophagectomy to avoid relapse [6, 7].

Differential Diagnosis List

Final Diagnosis

Oesophageal schwannoma

URL:	https://www.eurorad.org/case/12879
DOI:	10.1594/EURORAD/CASE.12879
ISSN:	1563-4086