Hot shoulder PET/CT lesion: Unusual presentation of tenosynovial giant cell tumor

We present a case of a tenosynovial giant cell tumor (TGCT) incidentally discovered at the shoulder on PET/CT, in a patient with history of thyroid cancer. Many documented cases of TGCT have been incidentally imaged by PET/CT and have been found to have varying levels of metabolic activity, however the shoulder location is unusual. This type of musculoskeletal lesion often has MRI characteristics, such as gradient echo blooming, which can render a confident diagnosis without need for biopsy.