In many countries, including Anguilla, the month of October is used for creating a greater awareness of breast cancer. A better understanding of breast cancer, that includes identification of risk factors, adoption of screening measures, lifestyle changes, and improved treatment options, can lead to improved survival rates from breast cancer.
What is a risk factor?
A risk factor is anything that affects your chance of getting a disease such as cancer. Different cancers have different risk factors. For example, smoking is a risk factor for cancers of the lung, mouth, larynx (voice box), bladder, kidney and several other organs. Having a risk factor, or even several, does not mean that you will get the disease or cancer.
Some risk factors, like a person’s age or race, cannot be changed. Others are linked to cancer-causing factors in the environment. Still others are related to personal behaviours such as smoking, drinking and diet. Some factors influence risk more than others, and your risk for breast cancer can change overtime due to factors such as aging or lifestyle.
A breast cancer risk factor is anything that makes it more likely you will get breast cancer. Having one risk factor, or even several breast cancer risk factors does not necessarily mean you will develop breast cancer. Many women who develop breast cancer have no known risk factors other than simply being women.
What are some risk factors for breast cancer?
There are numerous risk factors for breast cancer – some we cannot change, while others we can definitely change.
Risk factors you cannot change include the following:
Gender
Simply being a woman is the main risk factor for developing breast cancer. Men can develop breast cancer, but this disease is about 100 times more common among women than men. This is probably because men have less of the female hormones, oestrogen and progesterone, which can promote breast cancer cell growth.
Aging
The risk of developing breast cancer increases as one gets older. About 1 out of 8 invasive breast cancers are found in women younger than 45, while about 2 of 3 invasive breast cancers are found in women age 55 or older.
Genetic risk factors
About 5% to 10% of breast cancer cases are thought to be hereditary, meaning that they result directly from gene defects (called mutations) inherited from a parent.
BRCA1 and BRCA2: The most common cause of hereditary breast cancer is an inherited mutation in the BRCA1 and BRCA2 genes. In normal cells, these genes help prevent cancer by making proteins that keep the cells from growing abnormally. If you have inherited a mutated copy of either gene from a parent, you have a high risk of developing breast cancer during your lifetime.
Although in some families with BRCA1 mutations the lifetime risk of breast cancer is as high as 80%, on average this risk seems to be in the range of 55 to 65%. For BRCA2 mutations the risk is lower, around 45%.
Breast cancers linked to these mutations occur more often in younger women and more often affect both breasts than cancers not linked to these mutations. Women with these inherited mutations also have an increased risk for developing other cancers, particularly ovarian cancer.
Genetic testing: Genetic tests can be done to look for mutations in the BRCA1 and BRCA2 genes (or some other genes linked to breast cancer risk). Although testing may be helpful in some situations, the pros and cons need to be considered carefully.
Family history of breast cancer
Breast cancer risk is higher among women whose close blood relatives have this disease. If your mother, sister or daughter was diagnosed with breast cancer, particularly at a young age, your risk of breast cancer is increased. Still, the majority of people diagnosed with breast cancer (over 85%) have no family history of the disease.
Personal history of breast cancer
A woman with cancer in one breast has a 3- to 4-fold increased risk of developing a new cancer in the other breast or in another part of the same breast. This is different from a recurrence (return) of the first cancer.
Dense breast tissue
Breasts are made up of fatty tissue, fibrous tissue and glandular tissue. Someone is said to have dense breast tissue (as seen on a mammogram) when she has more glandular and fibrous tissue and less fatty tissue. Women with dense breasts have a higher risk of breast cancer than women with less dense breasts. Unfortunately, dense breast tissue can also make mammograms less accurate.
A number of factors can affect breast density: age, menopausal status, the use of drugs (such as menopausal hormone therapy), pregnancy and genetics.
Menstrual periods
Women who have had more menstrual cycles because they started menstruating early (before age 12), and/or went through menopause later (after age 55), have a slightly higher risk of breast cancer. The increase in risk may be due to a longer lifetime exposure to the hormones estrogen and progesterone.
Previous chest radiation
If you received radiation treatments to your chest, as a child or young adult, your risk of breast cancer is increased.
Women who, as children or young adults, had radiation therapy to the chest area as treatment for another cancer have a significantly increased risk for breast cancer. The risk of developing breast cancer from chest radiation is highest if the radiation was given during adolescence, when the breasts were still developing. Radiation treatment after age 40 does not seem to increase breast cancer risk.
Diethylstilbestrol exposure
From the 1940s through the 1960s some pregnant women were given the drug diethylstilbestrol (DES) because it was thought to lower their chances of miscarriage (losing the baby). These women have a slightly increased risk of developing breast cancer. Women whose mothers took DES during pregnancy may also have a slightly higher risk of breast cancer.
Risk factors related to lifestyle
There are several risk factors related to our lifestyle that are associated to breast cancer. These include the following:
Having children
Women who have had no children, or who had their first child after age 30 have a slightly higher breast cancer risk. Having many pregnancies and becoming pregnant at a young age reduce breast cancer risk. Pregnancy reduces a woman’s total number of lifetime menstrual cycles, which may be the reason for this effect.
Hormone therapy after menopause
Hormone therapy with estrogen (often combined with progesterone) has been used for many years to help relieve symptoms of menopause and to help prevent osteoporosis (thinning of the bones). Earlier studies suggested it might have other health benefits as well, but these benefits have not been found in more recent, better designed studies.
Combined hormone therapy: Using combined hormone therapy after menopause increases the risk of getting breast cancer. It may also increase the chances of dying from breast cancer. This increase in risk can be seen with as little as 2 years of use. Combined HT also increases the likelihood that the cancer may be found at a more advanced stage.
The increased risk from combined hormone therapy appears to apply only to current and recent users. A woman’s breast cancer risk seems to return to that of the general population within 5 years of stopping combined treatment.
Oestrogen therapy (ET): The use of estrogen alone after menopause does not appear to increase the risk of developing breast cancer. In fact, some research has suggested that women who have previously had their uterus removed, and who take estrogen, actually have a lower risk of breast cancer. Women taking estrogen seem to have more problems with strokes and other blood clots, though. Also, when used long term (for more than 10 years), ET has been found to increase the risk of ovarian cancer in some studies.
The decision to use hormone therapy after menopause should be made by a woman and her doctor after weighing the possible risks and benefits, based on the severity of her menopausal symptoms and the woman’s other risk factors for heart disease, breast cancer and osteoporosis. If a woman and her doctor decide to try hormones for symptoms of menopause, it is usually best to use it at the lowest dose needed to control symptoms and for as short a time as possible.
Breastfeeding
Some studies suggest that breastfeeding may slightly lower breast cancer risk, especially if it is continued for 1½ to 2 years. One explanation for this possible effect may be that breastfeeding reduces a woman’s total number of lifetime menstrual cycles (similar to starting menstrual periods at a later age or going through early menopause).
Drinking alcohol
The use of alcohol is clearly linked to an increased risk of developing breast cancer. The risk increases with the amount of alcohol consumed. Compared with non-drinkers, women who consume 1 alcoholic drink a day have a very small increase in risk. Those who have 2 to 5 drinks daily have about 1½ times the risk of women who don’t drink alcohol. Excessive alcohol consumption is also known to increase the risk of developing several other types of cancer.
Being overweight or obese
Being overweight or obese after menopause increases breast cancer risk. Before menopause your ovaries produce most of your estrogen, and fat tissue produces a small amount of estrogen. After menopause (when the ovaries stop making estrogen) most of a woman’s estrogen comes from fat tissue. Having more fat tissue after menopause can increase your chance of getting breast cancer by raising estrogen levels. Also, women who are overweight tend to have higher blood insulin levels. Higher insulin levels have also been linked to some cancers, including breast cancer.
But the connection between weight and breast cancer risk is complex. For example, the risk appears to be increased for women who gained weight as an adult but may not be increased among those who have been overweight since childhood. Also, excess fat in the waist area may affect risk more than the same amount of fat in the hips and thighs. Researchers believe that fat cells in various parts of the body have subtle differences that may explain this.
Physical activity
Evidence is growing that physical activity in the form of exercise reduces breast cancer risk. The main question is how much exercise is needed. In one study from the Women’s Health Initiative, as little as 1.25 to 2.5 hours per week of brisk walking reduced a woman’s risk by 18%. Walking 10 hours a week reduced the risk a little more.
What to do if you have one or more risk factors for breast cancer?
Even if you have a risk factor for breast cancer, it does not mean you will definitely get breast cancer. If you have a risk factor for breast cancer you should discuss this with your trusted doctor so that the appropriate screening tests, and timing of various medical examinations and screening tests/ investigations, can be arranged. In some cases you might need to change your diet and lifestyles, while in other cases various prophylactic measures might be needed. Breast cancer continues to affect women in Anguilla. In some cases early detection and improved treatments have led to improved survival rates, but much more is needed to see greater improvements in the survival rates for breast cancer in Anguilla.
Conclusion
Breast cancer in Anguilla, today, is not what it was 25 years ago. Survival rates are improving, thanks to greater awareness, more early detection and advances in treatment. The identification of various risk factors for breast cancer, and more individuals making lifestyle changes to decrease their risk factors, will certainly make a difference in the management of breast cancer. All individuals are encouraged to improve their knowledge of breast cancer and discuss with their doctor/health care provider ways to help in the fight against breast cancer.
Ask Your Doctor is a health education column and is not a substitute for medical advice from your physician. Dr Brett Hodge is an Obstetrician/Gynaecologist and Family Doctor who has over thirty years in clinical practice. Dr Hodge has a medical practice in the Johnson Building in The Valley.
