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Biomarker-Directed Approach to Guide Hormonal Therapy before Surgery for Patients with Stage II/III ER-Positive, HER2-Negative Breast Cancer

Trial Status: active

This phase II trial tests how well a biomarker-directed approach to guide endocrine (hormonal) therapy, such as with anastrozole, before surgery works for patients with stage II/III estrogen receptor (ER)-positive, human epidermal growth factor receptor 2 (HER2)-negative breast cancer. Although endocrine therapy and surgery are standard treatment for this type of breast cancer, responses to this treatment have been mixed. Researchers are looking for better ways to predict how people’s tumors will respond to endocrine therapy so that alternative treatments (such as chemotherapy) can be started to shrink the tumor better. Some tumors shrink well with endocrine therapy, yet others do not, and may need chemotherapy to shrink them better before the tumor is removed. One of the ways of predicting tumor response to treatment is testing tumor samples to look at genetic activity and molecular characteristics of the tumors to try to better determine which treatment might be the best to shrink the tumor. Using tissue testing to guide the selection of pre-operative treatment (endocrine therapy/anastrozole or chemotherapy) may work better to treat patients with stage II/III ER-positive, HER2-negative breast cancer.