Hormones and Breast Cancer

There are various types of breast cancer and 70% of them are sensitive to the female sex hormone, estrogen. These types of breast cancers are called estrogen receptor-positive cancers, or ER+ cancers. Essentially, these cancer cells have receptors that bind to estrogen, that grows and spreads. In addition, there are progesterone receptor-positive, or PR+, tumors that grow when exposed to progesterone. There are also breast cancer tumors that do not have receptors and there are known as hormone receptor-negative.

Estrogens are hormones that are produced in the ovaries and are necessary for sexual development and other bodily functions. However, postmenopausal women create this hormone in body fat, including the breasts. Levels of estrogen vary from woman to woman and fluctuate over time causing different symptoms and concerns. This is usually based on age and lifestyle factors.


For example, high levels of estrogen have been shown to be associated with an increased risk of breast cancer in postmenopausal women. Breast cancer is most commonly found in postmenopausal women and many of these cases are ER-positive. Fat cells in the breast produce larger amounts of an enzyme called aromatase, as a woman ages. The aromatase then encourages the production of estrogen. Eventually, with age, high levels of estrogen are present in a woman's breasts, that may result in the development and growth of breast cancer. Once a tumor is present, it promotes the production of estrogen to help it grow. In addition, immune cells boost the creation of estrogen as well.


Studies have also shown there is a clear link between obesity and estrogen production. This is due to the high amount of fat cells responsible for producing estrogens.

Treatments for breast cancer do vary and may include one or all of the following options…

  • Surgery A lumpectomy is the removal of the tumor and surrounding breast tissue. Or, mastectomy, the removal of the entire breast.

  • Radiotherapy Targeted x-rays that destroy cancer cells.

  • Chemotherapy Medications that destroy cancer cells.

  • Hormone Therapy may include… - Using medication to stop estrogen from helping the breast cancer cells to grow. - Using ovarian suppression medication to stop the ovaries from producing estrogen. - Using medication to stop estrogen production in fat cells.

Luckily, there are many lifestyle factors that can help prevent breast cancer or any cancer from developing. Habits like eating healthy, drinking water, and taking herbal supplements all contribute to healthy well-being and longevity.