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Neoadjuvant Endocrine Therapy to Improve Surgical Outcomes in Stage II-III ER+ HER2- Invasive Lobular Breast Cancer

Trial Status: active

This phase II trial tests the effect of endocrine therapy before surgery (neoadjuvant) on surgical margins in patients with stage II-III estrogen receptor positive (ER+) HER2 negative (-) invasive lobular breast cancer (ILC). Endocrine therapy, such as anastrozole, letrozole, exemestane, and tamoxifen, lowers the amount of estrogen made by the body, or blocks the use of estrogen by the tumor cells. This may help stop the growth of tumor cells that need estrogen to grow. Patients who are ER+ commonly receive endocrine therapy after surgery, including a lumpectomy, and/or radiation therapy to prevent the tumor from coming back. A lumpectomy is a type of breast conserving surgery (BCS) which involves removing the tumor and a small amount of normal tissue from the breast. Giving endocrine therapy before undergoing a lumpectomy may reduce the chance of having tumor cells at the edges of tissue removed during surgery (positive margins) in patients with stage II-III ER+ HER2- ILC.