[Bronchogenic cyst with atypical localization].

Bronchogenic congenital cysts are uncommon. They most frequently develop into the lung parenchyma. Rarely, mediastinal site may occur due to intestinal origin. Bronchogenic cysts seldom arise in the posterior mediastinum. Computerized tomography of the chest allowed a diagnosis of a posterior mediastinal bronchogenic cyst in our patient with poor symptoms. Cyst aspiration and MRI (magnetic resonance imaging) also provide the diagnosis. Treatment is by surgical excision if symptoms occur and have good prognosis.