A Case of Ectopic Cystic Thymoma / 결핵및호흡기질환

ABSTRACT

A thymoma commonly occurs in the superior mediastinum or the upper part of the anterior mediastinum but can be located in other places in rare cases. Cystic degeneration in a thymoma is a relatively common but focal event. In rare cases, the process proceeds to the extent that most if not all of the lesion becomes cystic. We report a case of a patient with a paracardial cystic thymoma in the lower aspect of the anterior mediastinum. A 49-year-old woman was referred to our hospital because of a mass discovered incidentally on a chest X-ray. She showed no symptoms or signs. Contrast-enhanced chest CT scan revealed a 5x5cm sized, well-marginated, right paracardial cystic mass with a curvilinear and oval enhancing solid portion. A Surgical resection was performed. The mass was discontinuous with normal thymic tissue. Microscopy revealed a type B1 thymoma with prominent foci of medullary differentiation according to the WHO classification. There was no capsular or local invasion. The postoperative course was uneventful and the patient was discharged in good health.