18F-FDG Whole-body PET/MRI of a 30-Week Pregnant Woman With Breast Cancer Revealed Interesting Fetal Findings

A 35-year-old 30-week pregnant woman was referred to our institution for initial staging of a triple negative invasive ductal carcinoma of the left breast. To avoid fetal radiation exposure from CT, a whole-body F-18-FDG PET/MRI was performed. Simultaneous acquisition of PET, T1-, T2-, and diffusion-weighted sequences revealed left axillary node extension and no distant metastases. Fetal radiation dose was estimated at 1.9 mGy. Interestingly, low fetal brain uptake and high symmetrical myocardial metabolism in both ventricles were found. Delivery was induced at 37 weeks of amenorrhea, and the patient underwent 4 cycles of neoadjuvant chemotherapy.