Pericardial cyst or teratoma? Change of strategy during mediastinal tumor surgery

This report describes the management of an 8 × 8-cm cystic mass that arose from the anterior mediastinum and prolapsed into the right pleural cavity adherent to the pericardium in an asymptomatic 16-year-old girl. The patient was scheduled for a video-assisted thoracoscopic operation with exposure, puncture and suction of a suspected pericardial cyst. However, during the procedure the strategy was changed due to the solid consistency of the mass, and the lesion was extirpated in toto by a short anterolateral thoracotomy. The complete histopathological investigation showed a highly fibrous, cystic, mature teratoma.