FDG PET/CT of carcinoma showing thymus-like differentiation.

Carcinoma showing thymus-like differentiation is a malignant, extremely rare neoplasm that arises in the thyroid gland or neighboring neck soft tissue and closely resembles thymic carcinoma. Long-term survival is possible if the disease is diagnosed early and is completely resected, followed by radical dose radiotherapy. We present the case report of a 65-year-old man who presented with neck mass and neck pain that increase with intensity with cough. He was evaluated by thyroid ultrasound, which showed an echogenic nodule. Baseline PET/CT imaging revealed a very hypermetabolic lesion in the right lobe of the thyroid gland.