Incidental Finding of Gastric Adenocarcinoma on F-18 FES PET/CT in a Patient With Breast Cancer

A 68-year-old woman with history of bilateral breast cancer was referred for F-18 fluoroestradiol (F-18 FES) PET/CT to evaluate sclerotic osseous lesions seen on surveillance CT scan. F-18 FES PET/CT showed no focal abnormal increased radiotracer uptake at the bilateral breast, and no suspicious radiotracer-avid lymph nodes or osseous lesions. The same F-18 FES PET/CT showed focal increased radiotracer uptake at the stomach fundus. A follow-up F-18 FDG PET/CT showed no suspicious focal hypermetabolic activity in the stomach. An endoscopic biopsy identified gastric adenocarcinoma.