Breast cancer

What is breast cancer?

One in every nine women in the UK will develop breast cancer at some point in her life - more than 45,000 cases are diagnosed each year. It has become the most common cancer in the UK, and is the leading cause of death for women aged 34 to 54.

Men can also develop this breast cancer.

Despite recent improvements due to better treatments and earlier detection, the UK still has one of the highest mortality rates for breast cancer in the world. But research is beginning to reap dividends in new ways of understanding how breast cancer cells work.

Breast cancer is a disease in which malignant (cancer) cells form in the tissues of the breast. Damage to the DNA of these cells results in uncontrolled cell division and growth, and, eventually, sufficient cells accumulate to form a lump.

The cells invade normal surrounding breast tissue and can break off from the primary lump to spread in lymph channels or the blood stream to other organs where secondary lumps (metastases) may form.

The breast is divided into ducts and lobules. The most common form of breast cancer arises from the ducts and is known as invasive ductal carcinoma. Cancers arising from the lobules (invasive lobular carcinomas) are less common.

As with most cancers, the key to successful treatment is early diagnosis before the cancer has had the chance to spread to other organs.

Breast cancer causes

The precise reasons why a woman develops breast cancer are still unknown, but are thought to be a combination of genetic, environmental and lifestyle factors. Scientists have identified two genes which are more likely to be defective in someone with breast cancer. These genes are also blamed for some other cancers. However, even the two mutated genes are thought only to be responsible for approximately five to 10 per cent of breast cancer cases.

Hormones seem to have an important role in breast cancer. Research has shown a link between oestrogen levels (the female sex hormone) and the risk of developing breast cancer. The exact causes of breast cancer have not been clearly identified, but there are certain risk factors:

• Getting older - 80 per cent of breast cancer cases are in postmenopausal women - it's relatively unusual in younger women
• Having a significant family history of breast cancer, which may be associated with inherited gene mutations
• Having no children or women who have their first child later in life
• Starting your periods early or going through the menopause late
• Certain types of hormone replacement therapy (HRT) for the menopause over a prolonged period
• Being overweight
• Drinking excess alcohol

Breast cancer and genetics

Fewer than one in 20 cases of breast cancer is inherited, so if a relative has breast cancer it's most likely to be by chance. However, you should be more wary if you have:

• A relative who was diagnosed under the age of 40
• A close relative with cancer in both breasts
• A male relative with breast cancer
• Two close relatives on the same side of the family diagnosed with breast cancer under 60 or with ovarian cancer
• Three close relatives diagnosed with breast or ovarian cancer at any age

It may be worth writing out a family health history record, to help you work out patterns of disease that run in the family.

Breast cancer protection

There is an increasing body of evidence to suggest that breastfeeding can protect you against developing breast cancer. It’s not known exactly how this occurs but a large study (150,000 women) by Cancer Research UK in 2002 compared the breastfeeding histories of women who had breast cancer with women who hadn't.

The results showed that the longer the women had breastfed during their lifetime, the less likely they were to get breast cancer, lowering risk by 4.3 per cent for every year of feeding and by 7 per cent for each child born and fed.

Breast cancer symptoms

The most common way that a potential problem is detected is when physical changes are noticed in the breast. The key is for the woman to know what 'normal' is - then changes can be noticed. All women should practise breast awareness. This involves getting to know what's normal for your breasts in terms of look and texture, so you can spot any changes and get them checked as soon as possible.

Examples of the kind of things to look out for include:

• Lumps or thickening of the tissue
• Any flaking skin or discharge from the nipple.
• 'Tethering' of the skin, as if it's being pulled from the inside
• Any unusual sensation or discomfort
• A change in outline, shape or size of the breast

Remember, although most lumps are harmless and will turn out not to be cancerous, you should still get them checked by a doctor as soon as possible, especially if you're young.

Many lumps will be picked up with mammograms - x-rays of the breast taken every few years as part of the NHS National Breast Screening Programme. The NHS National Breast Screening Programme provides free screening for breast cancer for all women over the age of 50. If you're between 50 and 70 you should be routinely invited for a mammogram every three years. Women over 70 are encouraged to make their own appointments. Regular breast screening may also highlight changes in the breast, enabling the condition to be diagnosed before any symptoms occur.

You may want to have a look at Macmillan's OPERA tool. This online risk assessment program has been designed to give information about your hereditary risk based on the your personal and family history of breast and ovarian cancer.

Diagnosing breast cancer

If a lump is found, techniques used to investigate it include using an ultrasound and mammogram. Doctors may take a sample of tissue using a needle. This is then analysed to assess whether malignant cells are present and confirm the diagnosis of cancer.

The cells may be tested to see if they carry certain receptors, which may influence the treatments offered. If they carry hormone receptors, it suggests they're sensitive to female sex hormones and hormone therapies are likely to be used in their treatment. Cells carrying the Her2 receptor may respond to the drug trastuzumab (herceptin), which may be used in the treatment of some Her2 positive cancers.

All patients suspected of having breast cancer must be seen by a hospital specialist within two weeks of an urgent referral by their GP. Some hospitals run 'one-stop shops' for rapid assessment of breast lumps where all the examinations can be done on the spot, often with the results available on the same day.

Inflammatory breast cancer (IBC)

IBC is a rare but aggressive type of breast cancer. The cancer cells block the lymph vessels that drain the breast tissue, making the breast swollen and inflamed. Symptoms, which often develop rapidly, include a red, swollen, warm breast, with bruised or pitted skin. The breast can be painful and you may be able to feel a distinct lump. See Breast Cancer Care for more detailed information.

Breast cancer treatments

If cancer is suspected, other investigations such as blood tests, chest x-rays and CT scans may also be done.

Once a diagnosis of breast cancer is confirmed, the exact treatment used, how soon it's given and how long it takes all depends on several factors, including:

• The stage of the tumour (how far it has spread) and whether there is secondary cancer
• The receptor status of the breast cancer
• Fitness and wellbeing
• If you've had the menopause
• Your own wishes on the treatments you may receive

Management of breast cancer is a team effort and a number of specialists may be involved including surgeons, oncologists and breast care nurses.

The bigger the tumour relative to the size of the breast, the more likely that a mastectomy will be recommended. In a procedure known as a ‘lumpectomy', just the cancerous lump is removed. After both kinds of operation, radiotherapy may be given to reduce the chance that the cancer will return. Most women with breast cancer don't need to have a breast removed.

If the tumour is very large, treatment may be given to reduce its size before the operation takes place. In most cases, the surgeon also removes lymph nodes under the arms to find out if cancer cells have spread into the lymphatic system (a network of vessels which link different parts of the body). If the cancer has reached the lymph nodes, it's more likely to have spread to other parts of the body.

The breast cancer cells may be tested to see if they are sensitive to oestrogen, and are more likely to grow if the hormone is present. If this is the case, you may be given a drug which blocks the action of the hormone, restricting the cancer growth. However, as some forms of this drug produce menopausal symptoms, younger women whose breast cancer is more likely to have spread could be offered a combination of surgery and chemotherapy instead.

Following breast surgery, or even breast removal, reconstructive surgery is possible to restore the appearance of the breast. This could even be carried out at the same time as mastectomy. Techniques have improved in recent years, and surgeons are able to more closely mimic the appearance of the other breast, giving a normal appearance in clothes.

Some of the techniques employed include the use of implants, fat from other parts of the body, such as the tummy, or even a back muscle which is bent round to form the new breast.

Secondary cancer

Cells may break away from a breast tumour and spread to another part of the body via the blood or lymph fluid. Often they die, or remain inactive, but sometimes they start to divide and form a new, secondary tumour, which may develop years later. The symptoms of secondary breast cancer very much depend on to which part of the body the cancer cells have spread.

Among the places where breast cancer cells tend to end up are:

• Lymph glands
• Bones
• Liver
• Lungs
• Brain (although this is less frequent)

Secondary breast cancer often only affects one part of the body. But it's possible for secondary breast cancer to affect more than one place at a time.