A Tale of 3 Tracers

Abstract A 41-year-old woman with invasive lobular carcinoma of the breast underwent sequential 68 Ga-PSMA-11 PET/CT and 18 F-fluciclovine PET/CT as part of an ongoing clinical trial (NCT04750473). 68 Ga-PSMA PET/CT showed increased radiotracer uptake in the uterine endometrium and left adnexa. 18 F-fluciclovine PET/CT showed increased radiotracer uptake in a leiomyomatous uterus. A clinical 18 F-FDG PET/CT demonstrated radiotracer uptake in the endometrium and a circumferential area of uptake in the left adnexa, a pattern more similar to the 68 Ga-PSMA uptake pattern. This case highlights the discordance in the uptake pattern of 2 radiotracers approved for prostate cancer imaging but increasingly used in non-prostate malignancies imaging.