Breast cancer is the most prevalent cancer in the UK, with around 48,000 new cases diagnosed in women in Britain each year. In the United States, breast cancer is the second most common cancer next to skin cancer, and the second leading cause of death from cancer next to lung cancer. The majority (about 80%) of individuals who develop breast cancer are over 50 years of age, although younger women and, on rare occasions, even men can develop the condition.
Cancer prevention describes any action taken to lower the risk of developing cancer. Although action cannot be taken against some risk factors such as a family history of breast cancer, other factors, such as lifestyle habits, can be modified to considerably lower risk. Some studies have shown this to be the case even among high risk individuals1.
Some of the lifestyle modifications an individual can adopt to help reduce their risk for developing breast cancer include:
The more alcohol an individual drinks, the greater the risk for breast cancer. Drinks such as beer, wine and liquor should be limited to no more than one a day.
An increasing amount of research has shown an association between smoking and breast cancer, particularly among women who have not yet experienced the menopause.
Being overweight or obese increases the risk of breast cancer, especially later in life, and particularly after the menopause. Overweight or obesity can increase oestrogen levels, which can in turn, increase the risk for breast cancer.
Physical activity can help maintain a healthy weight and therefore reduce the risk for breast cancer. A number of studies have demonstrated that moderate-to-vigorous physical activity is associated with decreased breast cancer risk3.
Studies have shown that women who choose to breastfeed are less likely to develop breast cancer than those who choose not to. The mechanism behind this is not clear but it has been suggested that those who breast feed ovulate less regularly, which keeps oestrogen levels stable.
Limiting the dose and duration of hormone therapy
Evidence from two randomized clinical trials into the use of menopausal hormonal therapy among women aged 50 to 79 suggests that taking a combination of estrogen plus progestin increases the risk for breast cancer5. If a patient decides that the benefits of short-term hormone therapy outweigh the risks, the lowest dose that works for them should be prescribed5.
Breast cancer and diet
A healthy diet rich in vegetables, fruit, fish, poultry, and low-fat dairy products has been associated with decreased breast cancer risk in some studies3 but it is unclear whether specific vegetables, fruits, or other foods can lower the risk and no studies have yet found that lowering fat intake particularly affects the risk. However, a healthy diet can help maintain a healthy weight, an important factor in preventing breast cancer.
Finding breast cancer early
Aside from lifestyle changes, another important action a woman can take to reduce their risk for breast cancer is to follow the guidelines for early detection. These include performing regular self-checks, consulting a physician on the discovery of any unusual lumps or skin changes, and openly informing the physician of any familial history of the condition.
Treatments to reduce risk
An individual’s breast cancer risk is determined on evaluation of factors such as age, familial history, and findings from physical examination or genetic tests. For women who are found to be at an increased risk because they have, for example, a strong family history of breast cancer, a known genetic mutation of a BRCA gene, or have been shown to have pre-cancerous changes in the breast, some treatments are available to reduce this risk. The two main treatments are surgical breast removal (mastectomy) and medication.
Mastectomy can be used to treat established breast cancer as well as to reduce the chances of developing the condition in high-risk individuals. By removing as much breast tissue as possible, a mastectomy can reduce the risk for breast cancer by up to 90%. An individual can usually choose to have a breast reconstruction either during the mastectomy, or at a later date. Breast prostheses or artificial breasts that can be worn inside the bra are another alternative.
In June 2013, the National Institute for Health and Care Excellence (NICE) announced that two medications, tamoxifen and raloxifene, will become available on the National Health Service that can be used to treat women who are at an increased risk for developing breast cancer2. NICE states that these treatments may help save breast cancer from developing in around 488,000 women aged 35 years and older.
Either of the drugs can be used by women who have been through the menopause but only tamoxifen should be used by women who have not. A course of preventative treatment with either drug would usually mean taking one tablet daily for five years.