This article answers some common questions about breast cancer and suggests where you can turn to for further information or advice.
Breast cancer affects one in eight women at some point in their lifetime. [1] Globally, more than one million women are diagnosed with breast cancer each year, making it the most common form of cancer in women. [2] This means that many people will be affected by breast cancer at one time or another, either personally or because a relative or friend is diagnosed with the disease.
Breast cancer occurs when cells within the breast begin to divide and grow in an uncontrolled way. This results in a mass of cells called a tumor. Not all tumors are the same – some are harmless (benign), but some can spread to other parts of the body through the bloodstream or lymphatic system and damage other tissues. These are known as malignant tumors.

Anatomy of the breast
Breast cancer is not a single disease – tumors can occur in the milk-producing glands or in the milk ducts, among other regions of the breast.
The various forms of breast cancer differ in important ways. Most crucially, some breast cancers are more likely than others to spread beyond the breast to other parts of the body. Other ways in which different breast cancers vary include:
How likely they are to respond to different treatments;
The likelihood that the cancer will recur;
Whether the cancer can be cured;
How quickly the tumor will grow.
Breast cancer affects women of all ages, races, nationalities, and backgrounds. Breast cancer can also affect men, although it is around 100 times rarer than breast cancer in women. Although there is no typical breast cancer sufferer, the disease is more likely to affect certain groups of people. For example, most breast cancers occur in older women – those aged 50 years and over. Breast cancer is also more common in women who have a close relative (mother, sister, or daughter) with the disease.
Risk factors are things that increase your likelihood of getting a disease. As described above, being a woman and getting older are the main risk factors for breast cancer. Other risk factors include:
Certain genetic mutations;
Having a family history of breast cancer;
Starting to menstruate early;
Going through the menopause late;
Long-term use of oral contraceptives;
Exposure to radiation;
Heavy alcohol consumption;
Being overweight.
From the list above, it can be seen that some risk factors for breast cancer are inherited (genetic) while others are related to lifestyle or the environment. This demonstrates that breast cancer does not have a single, specific cause. Instead, it arises from a complex series of events, many of which are still unknown.
It is important to realize that most women with the risk factors above will never get breast cancer. By the same token, around half of all women who develop breast cancer have no identifiable risk factor other than being an older woman. The best way to protect yourself is to change the risk factors where possible – such as cutting down on alcohol and keeping to a healthy weight – and staying well-informed to try to detect the tumor early.
Finding a tumor early significantly improves the chances of successful treatment. If breast cancer is found and treated before it has spread beyond the breast, the cure rate is more than 95%. [3] That’s why all women should become familiar with how their breasts feel normally, and at different times of the month, by regular self-examination. They will then quickly become aware of any unusual changes.
Many countries have breast cancer screening programs to help detect tumors at an early stage. These programs invite women in certain age groups – usually 50–69 years – to attend for a “screening mammography” at regular intervals. Mammography is a low-dose X-ray technique for examining the breast. It is especially useful for detecting early changes in the breast tissue that would not be noticeable by touch and feel alone.
Breast cancer screening programs have helped increase the number of women diagnosed with the disease and thus helped them obtain appropriate treatment. If you’re invited to attend for screening it is advisable that you attend. Usually only older women are invited to attend screening programs, but all women should be “breast aware”.
Be breast aware: Examine your breasts regularly
If you notice anything unusual about your breasts you should see your doctor straight away. Your doctor will examine you, talk to you about your medical and family history, and determine whether you need to undergo further tests. Your doctor can also show you how to examine your breasts and tell you what to look out for.
While your doctor should always be the first port of call if you’re worried about breast cancer, there are many other places you can go for more information. Many countries have national organizations specifically set up to help people with cancer and their families. Such organizations generally provide up-to-date medical information, practical advice and support delivered via websites, telephone helplines, and written material. A selection of organizations and websites you could visit for more information are listed in the “Additional Information” section below.
1. Fay, M.P., Pfeiffer, R., Cronin, K.A., et al. Age-conditional probabilities of developing cancer. Statistics in Medicine. 2003; 22(11): 1837-48.
2. Bray F., McCarron P., Parkin D.M. The changing global patterns of female breast cancer incidence and mortality. Breast Cancer Res. 2004; 6(6): 229-39.
3. The Breast Cancer Interactive website. (AstraZeneca). Accessed September 25, 2006.
Cancer Research UK
United States National Cancer Institute
Breast Cancer Care
National Breast Cancer Coalition
Breast Cancer Action
Medline Plus
American Cancer Society
Cancer BACUP
European Breast Cancer Coalition
BreastNet
Association for International Cancer Research