Anterior mediastinal mass with hyperthyroidism; report of a case

The patient was a 27-year-old man who had been diagnosed as having hyperthyroidism and with an anterior mediastinal mass which was reduced in size after anti-thyroid therapy. This mass was thought to be thymic hyperplasia associated with hyperthyroidism. An anterior mediastinal mass accompanying hyperthyroidism should be surgically treated when it dose not regress after an appropriate antithyroid therapy or there is a clinical suspicion of malignancy.