causes of breast cancer
In most cases, we are not able to explain why a particular woman has developed breast cancer. There is a very complicated relationship between the way our genes work and the way we are affected by our environment.In a small (5%) of cases, there is an inherited gene mutation which makes a woman far more likely to develop breast cancer. Normally though, we are not able to show a definite cause.
There are some factors which may slightly increase a woman’s risk of developing breast cancer. This does not mean that if you have one of these factors that you will get breast cancer.
- Having had a previous breast cancer.
- Having had certain types of benign breast disease (lobular carcinoma in situ or atypical ductal hyperplasia).
- Women who are taking certain types of hormone replacement therapy (HRT), or have recently taken it, have a slightly increased risk of breast cancer. Younger women who take HRT because they have had an early menopause, or have had their ovaries removed, do not have an increased risk of breast cancer until after the age of 50.
- Taking the contraceptive pill very slightly increases a woman’s chance of developing breast cancer.
- Women who do not have children are slightly more likely to develop breast cancer then women who have children.
- Women who start their periods early (early puberty) or have a late menopause have a slightly higher risk of breast cancer.
- Women who have never breastfed are slightly more likely to develop breast cancer than women who have breast fed for more than a year.
- Being overweight, once you have had your menopause, can increase the risk of breast cancer.
- Drinking a lot of alcohol over many years can increase the risk of breast cancer.