A 27-year-old woman with ovarian immature teratoma underwent 18 F-FDG PET/CT for preoperative staging, which revealed intense FDG uptake in 2 distinct pelvic structures, mimicking primary endometrial cancer or metastasis. Although MRI showed no anatomic lesions in either uterus, it confirmed uterine didelphys—a rare Müllerian duct anomaly. This case illustrates that physiological menstrual uptake within a duplicated uterus can simulate malignancy. Clinicians must recognize such anatomic variants to avoid diagnostic pitfalls and accurately stage pelvic malignancies on PET/CT.
Yoon et al. (Mon,) studied this question.