Different Appearances of Esophageal Squamous Cell Carcinoma in 18F-PSMA PET/CT Versus 18F-FDG PET/CT

An 81-year-old man with a history of prostate cancer, status post radiation therapy, was referred for a prostate-specific membrane antigen (PSMA) PET/CT scan. Fluorine-18 DCF-Pyl (Pylarify) PSMA PET/CT showed focal increased radiotracer uptake at the right prostate and bilateral iliac chain metastatic lymph nodes. The same PSMA PET/CT showed focal increased radiotracer uptake at the junction of the mid to lower esophagus. 18 F-FDG PET/CT identified a large hypermetabolic esophageal mass in the mid to lower esophagus, showing a greater extent of esophageal disease than the PSMA PET/CT. An endoscopic biopsy confirmed poorly differentiated esophageal squamous cell carcinoma.