[Pericardiac tamponade revealing a lympho-epithelial thymoma (author's transl)].

An inaugural pericardiac tamponade performed on a 39 years old man, reveals a lympho-epithelial thymoma. The anatomic diagnosis first suggested by the radiography after evacuation of the effusion, is confirmed by the swab taken during the retroxiphoidal drainage. A 57 Gray cobaltotherapy was then performed.