Surgical procedure
The surgery by left posterolateral thoracotomy noted a dense adhesion between the masse and the chest walls, pericardium and left lung. The left lower lung lobe was completely deflated and incarcerated by the masse with islands of epithelial tissue, hair and calcified tissue. Anatomopathological findings led to the diagnosis of a mediastinal mature cystic teratoma. The patient was then transferred to the intensive care unit for three days and required a prolonged stay in the wards due to the collapsed left lung. She benefited with a flexible bronchoscopy twice with an insertion in situ of a chest tube for drainage. The chest tube was finally removed 15 days later after few trials of chest tube clamping followed by chest x-ray.