Breast Cancer

The word “cancer” comes from Latin and means “crab-like”. It is a purely descriptive term but has come to indicate an abnormal growth of cells where the initial control and repair mechanisms have broken down allowing these cells to grow and multiply without the normal constraints.

Cancers are those tumours that have the potential to break away from their proper location and spread to other parts of the body. Here they can disrupt the normal functioning of the areas they invade. Cancerous change can happen anywhere but it seems to be much more common in some organs than others.

The breast and lung cancer are the two most common cancers to occur in women. The incidence appears to have been steadily increasing for half a century, but it now looks as though it may have peaked and the tide may be turning in the right direction.

Breast cancer is almost unheard of under the age of 20, rare under 30 and uncommon under 40. Approximately two thirds of breast cancer occurs in women over the age of 50 and it becomes more and more common with increasing age. About 1 in 100 breast cancers occur in men.

Causes of Breast Cancer

There is no known cause of breast cancer. Some women are more likely to get breast cancer than others. It is estimated that between 1 in 12 or up to 1 in 8 women will develop breast cancer during their lifetime.

Less than 10% of breast cancers result from an identifiable inherited predisposition. The vast majority occur randomly and unpredictably. Women with a specific genetic mutation in the breast cancer genes (BRAC 1 and 2) have the highest lifetime risk of developing breast cancer which is estimated to be between 70 – 85% of those women who have been tested positive for this abnormal gene.

Where there is a very strong family history of breast cancer there is likely to be an increased risk even if an abnormal BRAC 1 and 2 genetic defect are not identified.

These risks can be determined accurately in our own Family History Clinic which is designed to provide information and guidance about those concerned about a family history of breast cancer.

Benign breast disease has been shown to be associated with a very slight increased risk of breast cancer. Women with some types of benign breast change such as epitheliosis are more predisposed than others. As far as the contraceptive pill is concerned the evidence keeps changing but it is probable there is a very slight increased risk in breast cancer in present users and up to ten years following use of the contraceptive pill.

In women taking HRT the evidence is a little clearer. The risks are not significant with under five years of usage but are definitely significantly increased (albeit slight) after taking HRT for ten years or more.

There is no conclusive evidence that any dietary factors either predispose or protect from the development of breast cancer. Nevertheless, healthy eating is always recommended.
Smoking has so many ill effects on health, the most important of which is the increased risk of lung cancer and heart disease, but as far as breast cancer there is no consistent evidence of an increased risk.

Lifetime oestrogen exposure probably influences the risk of breast cancer developing very slightly. Women who have an early menarche (start their periods at an early age) and have a late menopause have an increased lifetime exposure to oestrogen which may be associated with a small but significant increased risk of developing breast cancer.

Breast feeding seems to protect against the development of breast cancer, but it is important to mention that with any of these risk factors you can breast feed several babies and still get breast cancer and breast feed none and never get it at all.

Obesity appears to be associated with a slight increased risk of developing breast cancer.
Alcohol consumption has recently been shown to be associated with a slight increased risk and it is likely with increasing amounts of alcohol consumed the risk of breast cancer increases.

Radiation can represent a risk of developing breast cancer. For young women who have received so called “mantle” radiotherapy for lymphomas there is a very definite increased risk of breast cancer .

There have been theoretical concerns that repeated mammograms might predispose to the development of breast cancer, but there has never been any evidence of this and the doses of radiation in modern mammography are very low indeed.

It should be emphasised that apart from carrying the abnormal genes mentioned above, the biggest risk factor for developing breast cancer is getting older.

Symptoms of Breast Cancer

Most breast cancers present with a painless lump and any woman finding a new lump in her breast needs urgent medical advice and should arrange to see her doctor as soon as possible.
Some breast cancers present with changes in the shape of the breast with distortion or dimpling seen in the skin or changes in direction that the nipple is pointing.

Nipple inversion is usually associated with benign changes but can be caused by an underlying cancer. Similarly, most nipple discharges have an innocent origin, but spontaneous bloody discharges need full assessment.

Enlarged glands in the armpit (axilla) can represent spread to the lymph nodes (or lymph glands) and occasionally these are discovered before the breast lump has been found.

Nowadays many breast cancers are found before they have produced any symptoms at all, through the Breast Screening Programme.

The outlook for women diagnosed with breast cancer has improved dramatically over the past two decades.

The reasons for these improved cure rates are earlier diagnosis by screening and by women being more breast aware and reporting abnormal findings straightaway. Additionally team working has been a tremendous advance in dealing with all cancers, but it was breast surgeons that led the way to specialised multidisciplinary clinics. 

Improved and appropriate surgery, radiotherapy given consistently, when indicated, and adjuvant systemic treatments have all been important in improving outcomes. Drug treatment has advanced fantastically over the past two decades. Drug treatments includes hormone manipulation such as Tamoxifen which is a selective oestrogen receptor modulator (SERM). It blocks the effect of oestrogen on the breast and improves survival in women whose tumours are oestrogen receptor (ER) positive. All cancers of women treated get tested routinely for their oestrogen receptor and progesterone receptor status and their HER2 status which helps to establish whether the new drug Herceptin may be indicated.

Aromatase inhibitors are drugs which inhibit the formation of oestrogen in post-menopausal woman and provide an alternative to Tamoxifen in this group.

The use of chemotherapy has become extended to more and more women as new research becomes published and the improvements in responses to new combinations has been one of the greatest recent advances in preventing women from dying of breast cancer.