For stage III breast cancer, should surgery or chemotherapy come first? The success rates of these two treatments. If it's stage III, most of the patients will receive chemotherapy before surgery. Doing chemotherapy first can shrink your tumor, reduce the tiny tumors in your blood, reduce the chance of recurrence, and help you provide the opportunity to preserve your breasts. It can also know your sensitivity to drugs. If you can't control the tumor after chemotherapy, it means your prognosis is very poor. In this case, it's recommended to do chemotherapy first and then surgery.