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What is Hormone Receptor- Positive Breast Cancer?(1)
In this type of breast cancer, the receptors for the hormones estrogen and progesterone are produced in excess within cancer cells.
When estrogen is overproduced, the cancer is known as Estrogen Receptor-Positive or ER-positive. When progesterone is overproduced, the cancer is known as Progesterone Receptor-Positive, or PR-positive. These hormones encourage cells to grow and divide, and present in excess, they cause uncontrolled growth and when present result in the formation of a tumour.
References:
(1) WebMD. Types of Breast Cancer. 2020. Available at: http://www.webmd.com/breast-cancer/breast-cancer-types-er-positive-her2-positive [Accessed May 2021]