Breast cancer prevention
Structure of the breast
The fight against breast cancer starts with knowing your breasts. They are made up of fat, nipple, milk glands (alveoli) and a network of ducts through which milk can pass from the glands to the nipples. Breast cancer can form in the milk ducts, milk glands, connective tissue or fatty tissue, although about 99 per cent of all breast cancers begin in milk ducts or milk glands. Breast tissue cells normally multiply and grow at a controlled pace. When these cells mutate and replicate without stopping, a mass of excess tissue, or tumour, is formed. Tumours can be benign (non-cancerous) or malignant (cancerous).
Each breast also has blood vessels and vessels that carry lymph (colourless or slightly yellowish body fluid) to organs called lymph nodes. Clusters of lymph nodes are located under your arms, above your collarbone and in your chest, as well as other strategic places in the body. Cancer can spread from the breast to other parts of your body via the lymph nodes or bloodstream. Cancer is said to have ‘metastasised’ when it has escaped the breast tissue and has begun to grow in other organs.
Can you prevent breast cancer?
To date, there is still no known absolute measure to prevent breast cancer. Sometimes, in extreme cases, women who are at extremely high risk of developing breast cancer (say from a strong family history or having one of the genes that increase risk) have made the decision to have preventive surgery and have both breasts removed, even though there were no signs of cancer at the time. This reduces their risk of developing breast cancer by 90 per cent or more. Taking medicines that block the effect of oestrogen in the body (e.g. raloxifene) is another way that women at very high risk of breast cancer can reduce their risk.
Although you can’t do anything about a positive family history of breast cancer and you can’t stop ageing, both of which are risk factors for developing breast cancer, you can always take defensive measures to protect yourself. These include having regular screening and doing regular breast examinations yourself to familiarise yourself with your breasts.
You can also change any lifestyle factors which seem to have an effect on breast cancer risk, such as alcohol consumption.
Mammograms
BreastScreen Australia states that regular 2-yearly mammograms are the best way for women aged 50-69 to detect breast cancer early, which improves the chances of successful treatment and recovery. So, BreastScreen Australia provides free screening mammograms to women aged 50-69 years. There are more than 500 screening locations around the country including mobile units.
Although the scientific evidence is not strong enough to recommend regular screening mammograms for women aged 40-49 (unless they have a family history of breast cancer) they may request a free screening mammogram at BreastScreen Australia.
Women over 70 are also eligible for free screening mammograms through BreastScreen Australia.
The breast tissue in women before the menopause is dense and makes mammograms difficult to read, so women under 40 do not usually have regular screening mammograms.
There are other screening mammogram services apart from BreastScreen Australia, so talk to your doctor if you think you need a mammogram.
Exercise
Research suggests that undertaking regular exercise and maintaining a healthy body weight decreases the risk of developing breast cancer.
Diet
Advice to lower risk of breast cancer generally follows that of other cancers and includes controlling weight, especially after menopause, and eating a healthy diet. Increased intake of some dietary components, such as phytoestrogens (such as found in soy), fibre, lycopene (an antioxidant found in tomatoes), and vitamins A (e.g. from beta carotene), C and E, is said to lower the risk of breast cancer. These claims are controversial — studies have produced mixed results, although there is no doubt that a varied diet rich in fruit and vegetables helps you stay healthy.
You can, however, reduce your risk by not having alcohol every day. Having more than 2 standard drinks of alcohol per day is associated with an increased risk of breast cancer, and the risk is further increased with each additional standard drink per day.
Last Reviewed: 10 April 2009
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