Cancer prevention is action taken to lower the chance of getting cancer. To prevent new cancers from starting, risk factors and protective factors are looked at.
The following risk factors may increase the risk of breast cancer:
- Estrogen (endogenous): Endogenous estrogen is a hormone made by the body. Being exposed to it over a long time may increase the risk of breast cancer. Exposure to estrogen is increased in the following ways: early menstruation, late menopause, and/or late pregnancy or never being pregnant.
- Hormone replacement therapy (HRT or HT): Estrogen, progestin, or both may be given to replace the estrogen no longer produced by the ovaries in postmenopausal women or women who have had their ovaries removed.
- Exposure to Radiation: The risk of developing breast cancer depends on the dose of radiation and the age at which it is given. The risk is highest if radiation treatment was used during puberty.
- Obesity: Obesity increases the risk of breast cancer in postmenopausal women who have not used hormone replacement therapy.
- Alcohol: Drinking alcohol increases the risk of breast cancer. The level of risk rises as the amount of alcohol consumed rises.
- Inherited Risk: Women who have inherited certain changes in the BRCA1 and BRCA2 genes have a higher risk of breast cancer, and the breast cancer may develop at a younger age.
The following protective factors may decrease the risk of breast cancer:
- Exercise: Exercising four or more hours a week may decrease hormone levels and help lower breast cancer risk.
- Estrogen (decreased exposure): Exposure to estrogen is reduced in the following ways: pregnancy, breast-feeding, ovarian ablation, late menstruation, and/or early menopause.
- Selective estrogen receptor modulators: Selective estrogen receptor modulators (SERMs) are drugs that act like estrogen on some tissues in the body, but block the effect of estrogen on other tissues.
- Prophylactic mastectom:- Some women who have a high risk of breast cancer may choose to have a prophylactic mastectomy (the removal of both breasts when there are no signs of cancer).
- Prophylactic oophorectomy: Some women who have a high risk of breast cancer may choose to have a prophylactic oophorectomy (the removal of both ovaries). This decreases the amount of estrogen made by the body.