Breast Cancer and Hormone Therapy

There are many different types of breast cancer. Many breast cancer tumors—around 70% to 80%—have receptors for hormones like estrogen and progesterone. These receptors bind to their respective hormones, helping the tumor to grow. Because of this, hormonal therapies are often used to combat these types of tumors. Hormone therapy uses drugs to slow or prevent the growth of hormone-sensitive tumors by either blocking the body’s ability to produce a specific hormone (typically estrogen) or by interfering with its effects on breast cancer cells.