Breast cancer is the most common cancer (after skin cancer) in women worldwide – second most common cancer overall. This is why breast cancer risk factors are very important to know and it is also important for breast cancer prevention strategies.
According to oncologists, 1 in 8 women will develop invasive breast cancer over the course of her lifetime – about 1.5-2.0 million new cases diagnosed every year. This represents about 12% of all new cancer cases and 25% of all cancers in women.
Medical statistics confirmed that frequency of breast cancer can be different in different countries and continents which can be explained by quality of medical services and early diagnostics in some countries and by very specific eating habits in other countries.
It is well known that Belgium has the highest rate of breast cancer, followed by Denmark and France. At the same time, the lowest incidences of breast cancer cases were noted in Asia and Africa.
Breast cancer survival rates are also different – Belgium is known by its highest proportion of breast cancer survivors still alive 5 years after their diagnosis and highest breast cancer survivors after 10 years. Denmark and France shared second and third places in competition for breast cancer survivors. Northern America and Europe also have pretty high frequency of breast cancer survivors. The lowest incidence of breast cancer survivors was noted in Africa and Asia.
White women are slightly more likely to develop breast cancer than African-American women. It should be mentioned that in women under 45 breast cancer is more common in African-American women than white women.
Breast cancer incidence rates start decreasing in 2000. As breast cancer is hormone related, some experts explain it partially due to the reduced use of hormone replacement therapy (HRT) and reduced use of hormonal contraception in some developed countries. It also can be a result of treatment advances, earlier detection through screening and increased awareness campaigns.
Scientists discovered several links between breast cancer and lifestyle – strong connections with several breast cancer risk factors. It was noted that about 20-25% of breast cancer cases can be prevented if main well known breast cancer risk factors would be avoided.
Breast cancer risk factors
Breast cancer risk factors
The most significant risk factors for breast cancer is a gender – just being a woman is already a risk for breast cancer development. Breast cancer could be discovered not only in women but also in men. According to medical statistics, breast cancer occurs nearly 100 times more often in women than in men. At the same time, about 2000 men are diagnosed with breast cancer each year.
It was noted that Caucasian women (“white women”) are slightly more likely to develop breast cancer than are African American women. Some selective races have decreased risk of developing and dying from breast cancer – Asian, Hispanic and Native American women.
It is well known that women with breast cancer history in the family have increased risks – actually risk of breast cancer development doubles if woman has a first-degree relative (mother, sister, daughter or father) who has been diagnosed with breast cancer. It is important to know that risk increases if your relative was diagnosed before the age of 50. About 10-15% of breast cancers can be linked to gene mutations inherited from parents – mutations of the BRCA1 and BRCA2 genes are the most common.
Breast cancer development risks are pretty high in women with BRCA1 mutation (about 55-56%) and less in women with a BRCA2 mutation (about 40-45%). Unfortunately increased ovarian cancer risk is also associated with same genetic mutations.
Risks for men are much lower – in cases of BRCA2 mutations risk is about 6-7% and in cases of BRCA1 mutations even less.
If person (woman or man) have been diagnosed with breast cancer in one breast, unfortunately it is increasing risks of being diagnosed with breast cancer in the other breast in the future.
In most cases (about 85%) breast cancers occur in women who have no family history of breast cancer (no inherited mutations). But mutations could happen as a result of aging process – growing older is the second biggest risk factor for breast cancer. It was noted that 2 out of 3 women with invasive cancer are diagnosed after age 55 – in general, women over 55 are more likely to be diagnosed with breast cancer. Younger women (before 45-50) get breast cancer rare – about 10-15% from all cases.
According to recent studies, female hormone estrogen stimulates breast cell growth and exposure to estrogen over long periods of time can increase the risk of breast cancer development. This is why early menarche (before age 12), late menopause (after 55-60), late gestation (after 35) and other cases of exposure to increased levels of estrogens (hormone replacement therapy, hormonal contraception) are considered as risk factors for breast cancer development.
Hormone replacement therapy (HRT)
Long-term use of hormone replacement therapy after menopause increases the risk of breast cancer development and HRT can also increase the likelihood that the cancer may be found at a more advanced stage.
Recent studies discovered that long-term use of oral hormonal contraception (birth control pills) can increase risk for breast cancer development.
Diethylstilbestrol was popular in 1940-1971 – it was commonly used for miscarriage prevention. Later it was noted that diethylstilbestrol may slightly increase the risk of developing breast cancer. Women whose mothers took diethylstilbestrol during pregnancy may have a higher risk of breast cancer development.
Breast cancer risk factors
Dense breast tissue
Scientific tests confirm that having dense breast tissue can increase risk for breast cancer development and even can make lumps harder to detect. Dense breast tissue could be also a problem during regular mammography – sometimes mammography cannot identify early stages of breast cancer. Women with high breast density, less fatty tissue and more glandular and fibrous tissue could be at higher risk for developing breast cancer than women with less dense breasts.
Dense breast tissue cellular changes (hyperplasia, atypical grow, benign tumors) can also increase breast cancer risk.
Pregnancy and/or breastfeeding
In most cases pregnancy and breastfeeding reduce future breast cancer risks. Women who never had children or who had first pregnancy after 35 or who avoid breastfeeding have an increased risk of breast cancer.
Several studies demonstrated that breast cancer risk increases with the amount of alcohol women drink – risk increases with the amount of alcohol consumed.
Obesity is associated with increased risk of breast cancer (especially for menopausal women). Fat tissue is can be the main source of estrogen after menopause – having more fat tissue means having higher estrogen levels, which can increase breast cancer risk.
Bad not healthy diet can be a risk factor for breast cancer development. In general, low-fat diet rich in fruits and vegetables can be recommended. Special attention should be paid to Anticancer Diet.
It is well known that stress usually damage immune system which can trigger cancer development. Laboratory tests demonstrated that psychological stress can affect tumor’s ability to grow and spread. Generally speaking, several mechanisms during stress could play not only risk factor for breast cancer development but could also stimulate grow of breast cancerous cells.
There is evidence that women who do night time shift work are in increased risk of getting breast cancer. Scientists found the correlation between risk of breast cancer and melatonin (so called “hormone of darkness”), a hormone produced by the body to promote continued sleep. When levels of melatonin decrease, the body produces more estrogen, which is a known risk factor for breast cancer.
Smoking is associated with a small increase in breast cancer risk – scientific studies have found an increased breast cancer risk among women who smoke (especially if women start smoking before they have their first baby).
If girls in their childhood or adolescent period had radiation (exposure or treatment) to the chest area, it could significantly increase breast cancer risk.
Many experts believe that physical activities can reduce breast cancer risk. In general, sedentary lifestyle is a negative factor for breast cancer. Health professionals recommend at least 30 minutes exercises every day.
Long-term monitoring studies show that some women will develop breast cancer even without any known risk factors. At the same time, having risk factor does not mean you will get breast cancer for sure. But avoiding breast cancer risk factors would increase your chances for healthy future.
Nobody knows why one person develops cancer and another does not. Some scientists highlight genetic factors, others mention environment and geo factors (radiation, sunlight, “poisoned” food and water) and most…
During last decades the stress is becoming a “normal” part of women life – career development, home, children, professional activities, complicated relations, family responsibilities. Generations of modern women experience growing…
Disclaimer: It is strongly recommended to consult your doctor for professional advice. Above mentioned information and recommendations are just general and should be adapted to each person according to personal health indicators and status.