Monitoring Breast Cancer Immunotherapy Treatment With Advanced Positron Emission Tomography Magnetic Resonance Imaging (PET/MRI)

This clinical study will investigate the utility of Fludeoxyglucose (18F) fluoromisonidazole (FMISO), in patients diagnosed with triple negative breast cancer (stage II-IV disease), to monitor and predict the effect of immunotherapy. This is a parallel imaging study to current treatment strategies and no clinical decisions or outcomes will be based on the imaging. If promising, this data will be used to design larger trials. A total of 20 patients will be recruited for this study. This trial will not designate the participant's treatment plan; they will be eligible based on their treatment plan designated from their oncologist.

Inclusion Criteria: 1. Patients must be ≥ 18 years old and ≤ 75 years old 2. Triple negative breast cancer (TNBC) patients (biopsy-proven) stage II-IV eligible 3. \>50%Programmed death-ligand 1 (PD-L1) positive 4. Eligible for immunotherapy who are naïve to beginning any immunotherapy treatment 5. May not be pregnant or breastfeeding 6. Subjects must be willing to sign consent 7. Adequate creatinine clearance per institutional guidelines and within 30 days 8. Estimated life expectancy of greater than one year 9. Patients must have one lesion with RECIST measurable disease (greater than 1 cm in diameter, measured from diagnostic breast MRI or staging CT) Exclusion Criteria: 1. Inability to provide informed consent 2. Weight over 350 lbs., due to the scanner bore size 3. Lactating, known or suspected pregnancy. Women with child-bearing potential must a have a negative serum Human chorionic gonadotropin (β-hCG) pregnancy test within 48 hours or a negative urine β-hCG pregnancy test within 24 hours of each PET imaging study. 4. Contraindication for MRI study (e.g. non-removable metal implants or certain tattoos) 5. Unable to lie still on the imaging table for one (1) hour 6. contraindication for gadolinium-based contrast agent, ProHance (gadoteridol) 7. Have received immunotherapy in the neoadjuvant or adjuvant setting