What Are The Risk Factors Of Breast Cancer?
Many factors known to increase the risk of breast cancer are not variable, such as age, family history, early menarche and late menopause. However, some factors are modifiable, these include post-menopausal obesity, use of combined estrogen and progestin menopausal hormones, alcohol consumption and breast feeding. Many breast cancer risk factors affect lifetime exposure of breast tissue to hormones.
Hormones are thought to influence breast cancer risk by increasing cell proliferation, thereby increasing the likelihood of DNA damage as well as promoting cancer growth. Although breast cancer risk accumulates throughout a woman’s life, research suggests that the time between menarche and first pregnancy may be particularly critical. Many established risk factors for breast cancers are specifically associated with ER+/luminal breast cancer; less is known about risk factors for ER- or basal-like breast cancers.
Strategies that may help reduce the risk of breast cancer include:
- Maintaining a healthy weight and lifestyle post-menopause
- Engaging in regular physical activity
- Minimizing alcohol intake
The increased risk of breast cancer associated with the use of combined menopausal hormone therapy should be considered when evaluating treatment options for menopausal symptoms. Women who choose to breastfeed for an extended period of time may also lower their breast cancer risk. Treatment with tamoxifen or raloxifene can also reduce the risk of breast cancer among women at high risk.
The most common risk factors for breast cancer are listed below:
Breast cancer is about 100 times more common in women than men. This makes gender the largest single risk factor for this disease. Hormonal stimulation of highly responsive and vulnerable breast cells in women, particularly during the extra-sensitive period of breast development, is why breast cancer is much more common in women compared to men.
After gender, age is the most dominate risk factor for breast cancer, with the incidence rate increasing significantly as age increases. The aging process may be the biggest risk factor because, the longer we live, the more opportunities for genetic mutations in the body. As we age our bodies become less capable of restoring this genetic damage.
Women with a positive family history of breast cancer may be at an increased risk for the disease themselves, depending on the degree of relation to the family member with the disease. It is thought having a parent, or grandparent with the disease will approximately double ones risk. The increase in risk is even greater in families with pre-menopausal onset, bilateral disease, ovarian cancer or where multiple generations are affected. Despite this over 85 percent of women who get breast cancer do not have a family history of the disease.
Genetic Risk Factors of Breast Cancer:
Genetic or hereditary risk factors result directly form gene defects inherited from a parent. Inherited mutations in BRCA1 and BRCA2 are the most well studied breast cancer susceptibilities genes, accounting for 5 - 10 percent of all female breast cancers, and estimated 5 - 20 percent of male breast cancer and 15 - 20 percent of all familial breast cancers. These mutations are very rare in the general population, but occur slightly more often in certain ethnic or geographically isolated groups.
How can early detection help?
Though there are methods to reduce the risk of breast cancer, over a woman's life there is a 1/8 chance she will obtain the disease. To ensure the chance of survival for a woman is as high as possible, we must make sure women are diagnosed as early as possible and as accurately as possible. To do this we must find a way to combat the limitations of screening and introduce a diagnostic tool aimed at improving breast cancer detection, especially for women who obtain difficult-to-interpret screening results.