The main purpose of this study is to learn if adding a targeted therapy, trastuzumab (Herceptin®), to standard treatment with chemotherapy for early stage, HER2-low breast cancer, will prevent breast cancer from returning.
The findings of a previous study in breast cancer patients revealed that the addition of trastuzumab to combination chemotherapy helped prevent the cancer from coming back and improved the survival in women with HER2-positive breast cancer. (HER2 is a protein that is found on some types of cancer cells. Trastuzumab is a type of protein made in the laboratory that binds to and can kill HER2-positive cancer cells.) There is some indication it might also be effective in patients with HER2-low breast cancer. This study is being done to
learn more about using trastuzumab to treat HER2-low breast cancer.