PRIMARY OBJECTIVES:
I. To evaluate the feasibility of 68-Ga RM2 PET/MRI for identification of estrogen receptor positive primary breast cancer and metastases
OUTLINE:
Patients receive 68-Ga-RM2 intravenously (IV) and after 45 minutes undergo PET/MRI over 30-60 minutes.
After completion of study, patients are followed up at 24-72 hours, and then for 12 months.
Inclusion Criteria:
* ER+ breast cancer at initial diagnosis prior to surgery or at recurrence (at least one ER+ lesion based on results of biopsy).
* Able to provide written consent
* Karnofsky performance status of ≥ 50 (or Eastern Cooperative Oncology Group (ECOG)/World Health Organization (WHO) equivalent)
Exclusion Criteria:
* Less than 18 years-old at the time of radiotracer administration
* Inability to lie still for the entire imaging time
* Inability to complete the needed investigational and standard-of-care imaging examinations due to other reasons (severe claustrophobia, radiation phobia, etc.)
* Any additional medical condition, serious intercurrent illness, or other extenuating circumstance that, in the opinion of the Investigator, may significantly interfere with study compliance
* Renal function impairment preventing administration of MRI contrast
* Metallic implants (contraindicated for MRI)