Breast cancer

Breast cancer is caused by the uncontrolled growth of cells in your breast tissue. It's the most common cancer in women in the UK.

How cancer develops

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About breast cancer

Your breasts are made up of fat, connective tissue and gland tissue divided into lobes. The lobes are connected to your nipple by milk ducts. Breast cancer usually starts in the cells lining your milk ducts.

In the UK, breast cancer is the most common cancer in women, with over 48,000 women diagnosed each year. The risk of breast cancer increases with age – it's most common in women over 50. Men can also get breast cancer but this is less common, with about 300 men diagnosed each year in the UK.

Types of breast cancer

There are different types of breast cancer, named after the type of cell the cancer first occurs in and how far it has spread. The three most common types of breast cancer are described below.

• Ductal carcinoma in situ (DCIS) is the earliest possible type of breast cancer. The cancer cells are only found inside the milk ducts and haven’t spread into the breast tissue.
• Invasive ductal carcinoma (IDC) is breast cancer that has spread outside the milk ducts into the breast tissue. Eight in 10 women diagnosed with breast cancer have this type.
• Invasive lobular carcinoma (ILC) is breast cancer that starts in the lobes. One in 10 women diagnosed with breast cancer have this type.

Symptoms of breast cancer

Symptoms of breast cancer can include:

• a breast lump
• a change in your skin, such as dimpling
• a change in your nipple shape, such as turning inwards
• a rash on or around your nipple
• discharge from your nipple
• a change in breast size or shape
• a swelling or lump in your armpit

Being breast aware by checking your breasts regularly can help you spot any changes. These symptoms aren’t always caused by breast cancer but if you have them see your GP. If you do have breast cancer, the sooner you’re diagnosed and start treatment, the more successful it’s likely to be.

Around three out of 10 women with breast cancer have no symptoms and the cancer is found during breast screening. If you’re over 50, you may decide to attend breast screening every three years.

Causes of breast cancer

The exact reasons why you may develop breast cancer aren’t fully understood at present. However, there are certain factors that make breast cancer more likely. You're more likely to have breast cancer if you:

• are over 50
• started your periods early or your menopause late
• have never had children
• have had children, but your first pregnancy was at an older age – the younger you are when you have children, the lower your risk of breast cancer
• have never breastfed
• take a contraceptive pill containing oestrogen
• take hormone replacement therapy (HRT) for a long period of time – combined HRT (oestrogen and progesterone) is more likely to cause breast cancer than oestrogen-only HRT and the longer you take HRT, the more your risk increases
• have a family history of breast disease or breast cancer, or have had breast cancer before
• are overweight after the menopause

Diagnosis of breast cancer

Your GP will ask you about your symptoms and examine you. He or she may also ask you about your medical history.

Your GP will refer you to a specialist breast clinic if he or she suspects that you have breast cancer. At the clinic, a doctor or nurse may carry out:

• a breast examination to look for signs or symptoms of breast cancer
• an ultrasound or mammogram to look inside your breasts
• an ultrasound of the lymph nodes in your armpits
• a fine needle aspiration – your doctor will collect samples of the cells from your breast and lymph nodes in your armpits using a fine needle
• a breast biopsy – your doctor will take a small sample of breast tissue

If you have a fine needle aspiration or breast biopsy, the samples will be sent to a laboratory for testing to determine the type of cells and if these are benign (not cancerous) or cancerous.

If you’re diagnosed with breast cancer, you may need other tests, such as a chest X-ray or CT scan, to find out whether the cancer has spread anywhere else in your body.

For more information about diagnosing breast cancer, see our related topics.

Treatment of breast cancer

The type of treatment you have depends on your general health, your age, the position and size of the cancer in your breast, and how far it has spread. Your surgeon or oncologist will discuss your treatment options with you.

Surgery

Removing the affected tissue is usually the first treatment option. Depending on the position and size of the cancer, your surgeon may suggest either a lumpectomy or a mastectomy. A lumpectomy is where only the affected breast tissue (or lump) is removed, usually with some healthy tissue around it. A mastectomy is where the whole of your affected breast is removed. If you have a mastectomy, you may be offered surgery to have your breast reconstructed afterwards.

Non-surgical treatments

Non-surgical treatments may be used before surgery to help shrink the tumour or after surgery. These treatments may also be used to treat cancer that has spread or come back. Non-surgical treatments available for breast cancer are listed below.

• Radiotherapy uses X-rays to destroy cancer cells. A beam of radiation is targeted at the part of your body where the cancer has been found. The aim of the treatment is to destroy cancer cells with minimal damage to the surrounding healthy tissue. If you have a lumpectomy, you will also need radiotherapy to the remaining breast tissue.
• Chemotherapy uses medicines to destroy cancer cells. The medicines are usually injected into your vein. You may need one or more different medicines as part of your treatment. A chemotherapy course is made up of repeated cycles of treatment, usually a few weeks apart, over a period of several weeks or months. Chemotherapy can be used as a treatment for breast cancer that has spread or come back.
• Endocrine therapy uses medicines to block certain hormones. Hormones, such as oestrogen, can affect the growth of breast cancer cells. Taking medicines that block these hormones can treat some types of breast cancer.
• Biological therapy uses manufactured proteins (monoclonal antibodies) to block areas on the surface of cancer cells that trigger growth. You may be treated with the monoclonal antibody trastuzumab (Herceptin) if your cancer cells have high levels of the HER2 protein on the surface. About one in seven women with early breast cancer have HER2-positive cancer.

Prevention of breast cancer

You can help to reduce your risk of breast cancer by living a healthy lifestyle. This means eating a healthy, balanced diet, maintaining a healthy weight and if you drink alcohol, only drinking in moderation.

There is some evidence that vitamin D may help to reduce your risk of breast cancer but more research needs to be done to be certain. Read more about how vitamin D may protect against cancer. 

Breast screening

Regular breast screening can help to detect changes in your breast that may be an early sign of breast cancer. The NHS Breast Screening Programme invites all women between the ages of 50 and 70 for breast screening every three years. If you’re in your late 40s or up to 73 years old, you may also receive an invitation to attend screening.

It’s important that you think carefully about the risks and benefits of breast screening before making a decision about whether or not to have the test. See our information on breast screening for more information.
 

Help and support

Being diagnosed with cancer can be distressing for you and your family. An important part of cancer treatment is having support to deal with the emotional aspects, as well as the physical symptoms. Specialist cancer doctors and nurses are experts in providing the support you need. You may also find it helpful to see a counsellor or join a support group to meet others in a similar situation.

Produced by Stephanie Hughes, Bupa Health Information Team, July 2012.

For answers to frequently asked questions on this topic, see FAQs.

For sources and links to further information, see Resources.