Spontaneous hemorrhage of a thymic cyst in an adult: report of a case.

Mediastinal cysts account for about 19% of all mediastinal masses, and thymic cysts represent only about 1.5% of anterior mediastinal masses. Thymic cysts do not usually cause symptoms and are often found incidentally on routine chest radiography. We report the case of a thymic cyst that hemorrhaged into the mediastinum and the right pleural cavity, causing chest pain. The patient, a 55-year-old man, underwent emergency surgical resection and recovered uneventfully.