Phase III Trial of Brain MRI Surveillance in Stage IV Breast Cancer

Inclusion Criteria:

* Histologic diagnosis of breast cancer with documentation of ER/PR/HER2 status
* Radiographic evidence of stage IV extracranial disease enrolled within 60 days of diagnosis or starting first line therapy. HR+/HER2- patients may be enrolled within 60 days of starting 2nd line therapy as well.
* HR+ will be defined as ER and/or PR \> 10%. To be classified as HER2+ disease, overexpression of HER2 by either IHC or in-situ hybridization is necessary as defined by the ASCO / CAP Guidelines41. Triple negative will be classified as ER and PR \<10% and HER2-.
* Age ≥ 18
* Life expectancy ≥ 6 months
* Eastern Cooperative Oncology Group performance status ≤ 2
* Patients must be able to understand and the willingness to sign an informed consent for study procedures
* Stated willingness to comply with all study procedures and availability for the duration of the study

Exclusion Criteria:

* Prior diagnosis or treatment of brain metastases or leptomeningeal disease
* History of other non-breast malignancy requiring treatment with the exception of those with a negligible risk of metastasis or death (e.g., 5-year OS of \> 90%), such as but not limited to, non-melanoma skin cancers, stage I endometrioid uterine cancer, and others at the discretion of the PI
* Neurologic symptoms warranting standard screening brain MRI in the judgement of the treating physician at time of enrollment
* Indications warranting brain MRI for other neurologic conditions at time of study entry (including multiple sclerosis, stroke, traumatic brain injuries, epilepsy, hydrocephalus and pituitary gland disorders)
* Contraindication towards MRI with contrast
* Chronic kidney disease stage IV or V or end stage renal disease (CrCl \<30 ml/min)