The causes of breast cancer are not yet completely understood. Some women do seem to be at a higher risk of developing the disease. The risk of developing breast cancer increases as women get older. More than half of breast cancers occur in women over the age of 65.
A very small number (less than 5 in 100) of breast cancers are caused by an inherited faulty gene. The abnormal genes that can lead to an increased chance of developing breast cancer include BRCA1 and BRCA2. The following factors might indicate the possible presence of an inherited faulty gene within a family:
- breast cancer in two or more close members of the same family
- other cancers, especially cancer of the ovary and colon, as well as breast cancer, in members of the same family
- breast cancer in a close relative when under the age of 40
- a relative with breast cancer affecting both breasts.
Women who either have no children or had children late in life have a slightly increased risk of developing breast cancer. Women whose periods started when they were very young or whose menopause occurred late also seem to have an increased risk.
Some research studies have suggested that women who take the contraceptive pill have a very slightly increased chance of developing breast cancer compared with women who have never taken the pill. However taking the pill has no effect whatsoever on most women’s chances of getting breast cancer.
Taking hormone replacement therapy (HRT) slightly increases the risk of developing breast cancer. Women taking combinations of oestrogen and progesterone seem to have a greater increase in risk than women taking oestrogen alone. However, HRT has many benefits. These include reduction of heart disease and the thinning of the bones that can lead to fractures in later life. For this reason it is considered that for the first 10 years of use the benefits of taking HRT outweigh the slightly increased risk of developing breast cancer.
There is no evidence that damage to a breast (such as a knock) causes cancer. Breast cancer is not infectious and cannot be passed on to other people.
What are the symptoms?
In most women, breast cancer is first noticed as a painless lump in the breast. There are, however, other signs to be aware of:
- a change in the size or shape of the breast
- dimpling of the skin of the breast
- a lump or thickening in the breast
- a change in the nipple (it turns in) or develops a lump
- a bloodstained discharge from the nipple (very rare)
- a rash on the nipple or surrounding area (also very rare)
- swelling in the lymph nodes in the armpit.
How is breast cancer diagnosed?
Most people begin by seeing their family doctor (GP) or nurse. They will examine you and arrange for you to have any tests or x-rays that may be necessary. Your GP will refer you to hospital for specialist advice or treatment.
At the hospital the doctor will take your medical history before carrying out a physical examination. The doctor will examine your breasts and feel for any enlarged lymph glands under your arms and at the base of your neck. A chest x-ray and blood tests may also be taken to check your general health.
If you would prefer you can ask to see a woman doctor.
