RecruitingPhase 3Diagnostic testPhase III Trial of Brain MRI Surveillance in Stage IV Breast CancerThis randomized, multi-institutional phase III trial evaluates whether routine surveillance brain MRI every 6 months improves detection and treatment characteristics of brain metastases in neurologically asymptomatic patients with stage IV breast cancer. Patients are stratified by receptor subtype, age, prior therapy, and study site, then randomized 1:1 to either scheduled surveillance MRIs or standard-of-care symptom-triggered imaging. The study aims to determine whether earlier detection leads to differences in treatment modality, frequency of brain metastases, leptomeningeal disease incidence, quality of life, and survival outcomes.