S1703, Randomized Non-Inferiority Trial Comparing Overall Survival of Patients Monitored with Serum Tumor Marker Directed Disease Monitoring (STMDDM) versus Usual Care in Patients with Metastatic Hormone Receptor Positive HER-2 Negative Breast Cancer

This randomized research trial studies how well serum tumor marker directed disease monitoring works in monitoring patients with hormone receptor positive Her2 negative breast cancer that has spread to other places in the body. Using markers to prompt when scans should be ordered may be as good as the usual approach to monitoring disease.