Phase II Short-term Adjuvant Therapy and Biomarker Studies With Targeted Agents in Women With Estrogen Receptor Negative Breast Cancer

The goal of this clinical research study is to learn if dasatinib can help prevent breast cancer from developing in the unaffected breast. Dasatinib is designed to decrease the activity of one or more proteins that are responsible for the uncontrolled growth of tumor cells. This is an investigational study. Dasatinib is FDA approved and commercially available for the treatment of leukemia. Its use in breast cancer patients in investigational. Up to 66 patients will take part in this multicenter study. Up to 60 will be enrolled at MD Anderson.