Bicornuate Uterus With FAPI Uptake Mimicking Ovarian Metastasis.

A 48-year-old woman with a history of colon cancer presented with abdominal pain and elevated tumor markers. She underwent 68 Ga-FAPI and 18 F-FDG PET/MR examinations. FAPI imaging revealed focal uptake in both adnexal regions, while no abnormal FDG metabolism was observed. Combined with a known history of uterine malformation, this uptake was confirmed to be physiological FAPI avidity in the benign myometrium of a bicornuate uterus, rather than ovarian metastasis. This case highlights the value of FDG-PET in ruling out malignancy and the importance of multi-tracer imaging in differential diagnosis.