Cancer

Breast cancer occurs when abnormal cells in the breast divide and grow out of control. There are several different types of breast cancer. Put very simply, the type of breast cancer depends on where it starts growing. Each breast contains 15 to 20 lobes, surrounded by fatty tissue, where milk is produced for breastfeeding. Milk gets to the nipple through ducts, or tubes, and there are about 30 in each breast. Cancer that starts in the lobes is called lobular cancer (or carcinoma). Cancer that starts in the ducts is called ductal cancer (or carcinoma).

Some breast cancers do not spread outside the lobes or ducts. This is called non-invasive or 'in situ'. So lobular carcinoma in situ (LCIS) or ductal carcinoma in situ (DCIS) are non-spreading forms of cancer. Most types of breast cancer can spread to other parts of the breast or body. This is called invasive. Non-invasive and invasive breast cancer can both occur at the same time.

When breast cancer spreads outside the breast it is called secondary breast cancer. The most common parts of the body it spreads to are the bones, the lungs, the liver or the brain.

Secondary breast cancer cannot be cured but there are treatments that can keep it under control, sometimes for years.

In the UK about 41,700 women and 300 men get breast cancer each year. Most people with primary breast cancer (breast cancer that has not spread elsewhere in the body) are treated successfully. With new and better treatments becoming available the chances of being cured are good and getting even better.

It is not known exactly what causes breast cancer although it probably results from complex interactions between our genes, lifestyle and environment. We do know some risk factors that increase your chances of developing the disease. For example, having a close relative who has had breast cancer. Also, your risk increases as you get older. There is also some scientific evidence to show that factors like your diet and how much exercise you do may alter your chances of developing breast cancer, but more research is needed. Oral contraceptives and hormone replacement therapy (HRT) may also cause a slight increase in risk of developing breast cancer.

Breasts change constantly from puberty, through adolescence, the childbearing years and then the menopause (change of life), and are affected by varying levels of the female hormone oestrogen. Most of these changes are perfectly normal, and not a sign of breast cancer.

It is a good idea to become breast aware. This means knowing how your breasts look and feel normally so that you are more confident about noticing any new or unusual changes, such as:

• A change in size - one breast may have become noticeably larger or noticeably lower
• A nipple has become inverted (pulled in) or its position or shape has changed
• A rash on or around the nipple
• Discharge from one or both nipples
• Puckering or dimpling of the skin
• A swelling under your armpit or around your collarbone
• A lump or thickening in your breast that feels different from the rest of the breast tissue
• Constant pain in one part of your breast or in your armpit

Medicines

Treatment for primary breast cancer aims to remove the cancer, to prevent it coming back and to stop it spreading to other parts of the body. Your treatments will depend on the exact nature of your breast cancer. Different tests will be done on the breast cancer to help decide what treatment will work best.

This is what affects which treatments are recommended:

• How big is the breast cancer?
• Where is the cancer in the breast?
• How close are the cancer cells to the borders of the area taken out? It is important that the cancer is removed with a rim of normal tissue around it to be sure that none has been left behind.
• What do the cancer cells look like? Doctors 'grade' cancer cells from one to three: grade 1 cancer cells look most like normal cells, grade 3 cells look most changed.
• Has the cancer spread to lymph nodes in the armpit? Fluid from the breast drains into the lymph nodes in the armpit so they are an obvious place to check for signs that the cancer has spread.
• Has the cancer spread to the tiny blood vessels in the breast?
• Does the breast cancer rely on the hormones oestrogen and progesterone to grow (known as hormone receptor positive breast cancer)?
• Do the cancer cells have high levels of a protein called HER2 that stimulates them to grow?

As well as tests on the breast cancer, sometimes you may need tests on your body (such as X-rays, scans and blood tests).

Everyone's treatment is tailored to their particular breast cancer. You may have surgery, chemotherapy, radiotherapy, hormone therapy or other treatments. You may have one or more of these, on their own or combined. Your medical team will explain your treatment and you will be able to ask them any questions you may have.

Surgery

There are two main types of surgery:

• Breast conserving surgery removes the tumour and surrounding tissue but leaves most of the breast. You may hear it called wide local excision or lumpectomy. You may also have surgery to the lymph nodes in your armpit.
• A mastectomy is when all the breast tissue is removed, usually including the nipple and some lymph nodes. If you have a mastectomy you may also choose to have a breast reconstruction, either at the same time or later.

Chemotherapy

Chemotherapy aims to destroy any cancer cells that may have spread from your breast to other parts of your body. This is done by exposing the whole body to anti-cancer drugs.

Hormone therapy

This is drug treatment that treats the whole body and stops the hormones oestrogen and progesterone from helping breast cancer cells to grow. It is also called endocrine therapy.

Radiotherapy

This is the use of high energy X-rays to destroy any cancer cells left in the breast area after surgery.

Other treatments

Targeted cancer therapies are drugs that work by blocking different ways in which breast cancer cells divide and grow. The most well known targeted therapy is Herceptin (trastuzumab) although others are being developed.

If you have any of the symptoms listed above, see your doctor. Do not worry about making an unnecessary fuss, and remember that most breast changes will not be cancer. Most will be normal changes or benign breast conditions, even if they sometimes do need treatment or follow-up.

Talk to your doctor about breast screening programmes. These are available free of charge on the NHS every 3 years to women aged 50 to 70. Breast screening is a way of finding abnormalities in the breast when they are too small to be seen or felt.