Hello: I underwent a thyrodichotomy in 2004 and I am taking 100 thyroxine, however, a thyroid remenents exist 10*10*6. The thyroid carcinoma was said to be medullary. Recently, I went a follow-up Neck and CT scan due to a pain in the chest and difficulty in swallowing. The Imagings reveal no evidence of enlarged cervical lymph nodes, however, the there is a 2 * 2.7 (mediastinal window) homogeneous hypodense soft tissue density lesion at the superior mediastinum with tiny peripheral clacification. What does this mean? Does it indicate a tumor in the chest, neck or lymph nodes? what should I do next?