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Tamoxifen Citrate, Letrozole, Anastrozole, or Exemestane with or without Chemotherapy in Treating Patients with Invasive RxPONDER Breast Cancer

Trial Status: closed to accrual and intervention

This randomized phase III clinical trial studies how well tamoxifen citrate, anastrozole, letrozole, or exemestane with or without chemotherapy work in treating patients with breast cancer that has spread from where it began in the breast to surrounding normal tissue (invasive). Estrogen can cause the growth of breast cancer cells. Hormone therapy, using tamoxifen citrate, may fight breast cancer by blocking the use of estrogen by the tumor cells. Aromatase inhibitors, such as anastrozole, letrozole, and exemestane, may fight breast cancer by lowering the amount of estrogen the body makes. Drugs used in chemotherapy work in different ways to stop the growth of tumor cells, either by killing the cells, by stopping them from dividing, or by stopping them from spreading. It is not yet known whether giving tamoxifen citrate, anastrozole, letrozole, or exemestane is more effective with combination chemotherapy in treating patients with breast cancer.