F-18 FDG PET/CT imaging of a subcutaneous scalp metastasis from primary carcinoma of the thyroid.

Abstract: Differentiated thyroid cancer frequently metastasizes but typically spreads to regional cervical lymph nodes and, in advanced cases, to the lungs and/or skeleton. Metastases to the skin/subcutaneous tissue are rare. We report a case of abnormal FDG uptake within a scalp metastasis on PET/CT in a patient with metastatic papillary thyroid carcinoma. Because thyroid cancer can rarely metastasize to the skin and particularly the scalp, attention should be given to that region during interpretation of the images.