NWHN’s Thoughts on Tamoxifen


What is NWHN's position on estrogen blockers when results of a lumpectomy show pre-cancerous micro cells in a duct?


Ductal carcinoma in situ (DCIS) is the medical term for “pre-cancerous” cells in the lining of a breast duct. It is important to understand that DCIS is not equivalent to breast cancer. It only means that the lumpectomy found abnormal cells that are not cancerous. There is no way to know whether these cells may progress into breast cancer. If the abnormal cells are estrogen-receptor positive that means its growth is stimulated by estrogen. In order to reduce the development of breast cancer, your health care provider may recommend tamoxifen.

Tamoxifen, also known as Nolvadex, is an antiestrogen drug that works by blocking estrogen in your body to stop abnormal cells from growing. Tamoxifen is associated with life-threatening health risks such as strokes, pulmonary emboli, endometrial cancer and uterine sarcoma. We encourage you to speak with your health care provider to determine whether you are at high risk for breast cancer. Additionally, your health care provider should discuss the potential risks and benefits of using tamoxifen for DCIS. For more information on tamoxifen and breast cancer risk, please refer to the Mayo Clinic’s Tamoxifen Fact Sheet.

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