2013 Volume 27 Issue 7 Pages 899-903
A 55-year-old man was referred to our department because of mild swelling of his neck. Computed tomography (CT) revealed a large anterior mediastinal mass (80×60×40 mm). Although CT-guided biopsy confirmed that the mass was not malignant, the possibility of a cystic thymoma or other neoplasm could not be ruled out; therefore, surgery was performed. Intraoperative rapid diagnosis suggested benignancy. However, as complete resection was difficult, part of the cystic lesion was left in situ. A histological diagnosis of multilocular thymic cyst (MTC) was established. Over a follow-up period of 10 years, the size and contours of the lesion remained unaltered. Recently, it was reported that MTC shows a strong association with thymoma and thymic cancer, and so this long-term follow-up period was justified.
