Non-neoplastic mediastinal cysts.

OBJECTIVE

The non-neoplastic mediastinal cysts (NNMCs) form a group of uncommon benign lesions of a congenital origin. The significant controversy regarding these cysts is whether to manage with observation or surgical resection. The aim of this study is to analyse the utility of thoracic computed axial tomography (CT) in imaging diagnosis of the NNMCs and the results of surgery in these lesions.

PATIENTS AND METHODS

Twenty NNMCs underwent surgery between 1980 and 2000. The preoperative study of mediastinal cystic masses includes a complete blood test, chest radiography (CR) and, for the last 15 years, a thoracic CT and/or nuclear magnetic resonance. All the patients underwent surgery in our thoracic surgery department and were reviewed in outpatients at 1 month, 6 months, 1 year and biannually thereafter. The form of manifestation, clinical features, imaging techniques, surgical operation, morbidity, mortality and follow-up are analysed.

RESULTS

Ten corresponded to bronchogenic cysts, the most common symptom of which was chest pain. CR showed a mass in the anterior-superior mediastinum in nine cases, and CT (five cases) revealed a cystic tumour in the anterior mediastinum. All were removed surgically, with three patients presenting with mild complications. Seven corresponded to pleuro-pericardial cysts, four being asymptomatic. CR showed a right paracardial mediastinal tumour, which was confirmed by CT (four cases). All were removed surgically, with two patients presenting with mild complications. Three corresponded to enteric cysts. CR showed a tumour in the posterior mediastinum, with CT confirming its cystic nature (two cases). Excision of the cyst was done in all cases, which corresponded to duplication cysts: two oesophageal and one gastric. All the patients are asymptomatic and recurrence-free after a follow-up of 11 +/- 10 years.

CONCLUSIONS

NNMCs are benign lesions in which the lesions in which the surgery can be done with a low morbidity and mortality rate, enables us to rule out malignancy and offers a definitive cure. Actually the thoracic CT permit a correct diagnosis pre-surgery in function of the radiologic characterisation and topography.