A Case of Mediastinal Ectopic Thyroid Tissue Diagnosed by Endobronchial Ultrasound Guided Transbronchial Needle Aspiration / 고신대학교의과대학학술지

ABSTRACT

A 77-year old woman was referred to hospital with dyspnea and chest dull pain for 5 months. The chest radiograph showed a mass located in the mediastinum. Trachea was deviated to right side. Chest computed tomography showed an enhancing large mass at the middle mediastinum. Endobronchial ultrasonography showed hyperechoic mediastinal mass. We performed endobronchial ultrasound guided transbronchial needle aspiration (EBUS-TBNA). Histologic finding was thyroid tissue with a benign looking papilla. Ectopic thyroid is an uncommon embryological aberration characterized by the presence of thyroid tissue in a site other than in its usual pretracheal region. It occurs along the path of descent of the developing thyroid primodium from the foramen cecum. It is extremely rare for mediastinal ectopic thyroid tissue diagnosised by EBUS-TBNA, so we report here on a case of mediastinal ectopic thyroid and we review the relevant medical literature.