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About Breast Cancer

In this section, you or a loved one can find out more about medical treatments, research studies and practical information about breast cancer. Read on to find answers to some of your questions as well as links to other information. Being informed is an important first step towards becoming an active decision-maker in your care plan.

What Is Breast Cancer?

Breast cancer is a cancer that originates in the cells of the breast. Before going into detail about this particular type of cancer, it is important to understand the basics. The body is made up of millions of cells. Each cell contains genes that are basically a set of instructions that tell the cell how to grow, work, reproduce and die. Cancer is a disease that affects the set of instructions in certain cells; as a result, the instructions can be changed and the cells become cancer cells. Cancer cells may grow too much, form lumps or malignant tumours, and potentially spread to other parts of the body.

People often consider breast cancer to be only one cancer. Actually, it is a group of different cancers that affect the breast. Knowing about the type of breast cancer you have can help you to understand what is happening in your body and how the treatment options prescribed by your doctor work.

The most common type of breast cancer is called ductal carcinoma because it starts in the cells of the milk ducts (or tubes) that carry milk from the glands to the nipple. Another common type of breast cancer starts in the group of glands that produce milk (lobules) and is called lobular carcinoma. Less common types of breast cancer include inflammatory breast cancer, Paget’s disease of the nipple, and triple negative and basal-like breast cancers.
What Causes Breast Cancer?

  • Most breast cancers occur in women, with less than 1% of the breast cancers occurring in men. The main reason is that female hormones, especially oestrogen, encourage the growth of some breast cancers.

    What are risk factors for breast cancer?

    Some of the factors that increase the risk of someone developing breast cancer include:

  • Family history of breast and other cancers
  • BRCA gene mutations – BRCA genes control how breast cancer behaves. There are 2 BRCA genes (BRCA1 and BRCA2). Mutations (abnormal changes) in these genes are rare and are typically inherited. Having mutations in one or both BRCA genes greatly increases the likelihood of developing breast cancer.
  • Ashkenazi Jewish ancestry (BRCA gene mutations are more common in Ashkenazi women)
  • Dense breasts
  • Rare genetic conditions produce genetic mutations in certain genes that suppress tumours, or that dispose one to certain types of cancers. These include: Li-Fraumeni syndrome, Ataxia- telangiectasia, Cowden syndrome, Peutz-Jeghers syndrome and the CHEK2 gene mutation
  •  Reproductive history
    o   Early start of first menstruations, late menopause, late pregnancy or no pregnancies increase the risk of developing breast cancer
    o Exposure to ionising radiation
  • Long-term (more than 5 years) use of hormone replacement therapy
  • Use of certain types of oral contraceptives for more than 10 years
  • Accumulation of abnormal cells in the breast (also called atypical hyperplasia)
  • Excessive use of alcohol
  • Being obese
  • Personal history of breast cancer

In order to prescribe treatment, doctors need to know the extent or “stage” of cancer in the body. For breast cancer, the most common staging system is the “TNM” system. TNM stands for tumour, nodes and metastasis. These are measured as follows:

  • Tumour: the size of the main tumour
  • Nodes: the number and location of any cancerous lymph nodes
  • Metastasis: determination as to whether or not the cancer has spread (metastasised) to other parts of the body


In breast cancer, there are five main stages: 0, I, II, III and IV. Generally, the possible outcome of the disease (prognosis) for the patient is better at lower stages. Very generally, the stages are:

  •  Stage 0: the cancer is only in the ducts, lobule or nipple and has not spread to nearby breast tissue, and is at an early stage.
  •  Stage I: the tumour is less than 2 cm in diameter; the cancer has not spread to the lymph nodes or other parts of the body.
  •  Stage II: A tumour larger than 2 cm but not more than 5 cm. Cancer may or may not have spread to the lymph nodes.
  •  Stage III: A tumour of any size. Cancer has not spread to other parts of the body but is in the lymph nodes.
  •  Stage IV: Cancer has spread to other parts of the body.

Generally, the earlier breast cancer is diagnosed and treated, the more likely the patient will survive. Your doctor can explain the statistics for breast cancer and what they may mean for you.

What are the effects of breast cancer?

The most common symptoms of breast cancer include:

A lump in the breast – the most common first sign

  • A lump in the armpit
  • Changes in breast shape or size
  • Breast skin changes
    o   The skin of the breast may become dimpled or puckered; this is sometimes called orange peel skin or peau d’orange.
    o   Redness, swelling and increased warmth (signs that look like an infection) or itching of the breast or nipple may be signs of inflammatory breast cancer
  •  Nipple changes
    o   Newly inverted nipple
    o   Discharge from nipples
    o   Crusting, ulcers or scaling on the nipple
  • Changes in lymph nodes
    o   Feeling for any lumps or other abnormalities
Are There Other Complications?

As the breast cancer gets larger or spreads to other organs, other symptoms may occur:

  • Bone pain
  • Nausea
  • Loss of appetite
  • Weight loss
  • Yellowing of the skin
  • Build-up of fluid around the lungs
  • Headache
  • Double vision
  • Muscle weakness
Lifestyle Options

For most people, regardless of having cancer or not, exercise, healthy eating and good sleeping habits are recommended. A healthy lifestyle can lead to an enhanced quality of life for most people. Talk to your doctor before making any lifestyle changes.

Physical activity can play an important role in your recovery from breast cancer. Benefits of exercise after breast cancer treatment can include:
  • Increased energy levels
  • Less fatigue, anxiety and depression
  • Reduction of stress
  • Improvement in cardiovascular fitness
  • Better self-esteem
  • Improved quality of life


Dietary supplements including vitamin, mineral or herbal supplements cannot take the place of healthy well-balanced eating. In some cases, however, your doctor or dietician will recommend supplements if you are deficient in a certain nutrient. It is important to note that taking vitamins or other supplements at a higher than recommended amount may do more harm than good and could even be dangerous. If you are thinking of taking a supplement, talk to your doctor first.

Complementary Therapy Options

Here are some examples of complementary therapies:

  • Acupuncture
  • Aromatherapy
  • Art therapy
  • Ayurvedic medicine (traditional approach that originated in India)
  • First nations healing
  • Massage
  • Naturopathic medicine
  • Traditional Chinese medicine
Medical Treatments

Your healthcare team will discuss your treatment options with you. These options may include: surgery, chemotherapy, hormonal therapy, biological therapy, radiation therapy and palliative care (treatment that relieves pain but does not treat the underlying condition).

Your healthcare team will consider a number of factors when deciding on a treatment for breast cancer, including:

  • Cancer stage
  • Whether menopause has been reached
  • Results from hormone receptor testing
  • Results of HER2 testing
  • Risk of recurrence
  • Overall health of the patient
  • Patient’s personal preference about certain treatments

Depending on the stage of your cancer and the treatment option(s) prescribed, you may have one or more of the following specialists on your healthcare team:

  • Surgical oncologist (surgeon who specialises in the treatment of cancer)
  • Radiation oncologist
  • Medical oncologist

Other healthcare professionals may also be involved, such as nurses and social workers.

Surgery is used to remove or repair body tissues in people with many different types of cancer, including breast cancer. It is the oldest cancer treatment and more than half of people with cancer will have some type of surgery. Breast cancer surgery removes the tumour and the lymph nodes in the armpit on the same side as the involved breast, and may be a lumpectomy or a total mastectomy (removal of the entire breast). Sometimes the breast is later reconstructed.
Chemotherapy involves the use of anticancer drugs. It is commonly used to treat breast cancer. Anticancer drugs (also called cytotoxic drugs) are designed to disrupt cancer cells. These drugs generally circulate through the entire body and even act against cancer cells that have broken away from the main tumour. Different chemotherapy treatments are available and are chosen based on the specific needs of a given patient. Antibody treatments that target specific proteins (HER2) on the cancer cell surface and interfere with cell signalling may also be used.
Hormonal therapy can help slow the growth and spread of breast cancer cells by changing hormone levels in the body or by stopping the breast cancer cells from using a specific hormone called oestrogen. Various means can be used to change hormone levels in the body; these include drugs, surgery or radiation. The use of hormonal therapy depends on whether your cancer contains receptors for oestrogen (ER) and progesterone (PR).
Radiation therapy utilises high energy X-rays to destroy cancer cells.

Please note that the information on this website is intended for informational purposes only and should not be used as a substitute for seeking medical advice or treatment from a healthcare professional. You should not use this information to diagnose or treat a medical condition or health problem. Speak to a health care professional if you have any questions about your health, medical condition, symptoms or treatment options.


Cancer Research UK is a cancer research and awareness charity in the United Kingdom

National Comprehensive Cancer Network

The National Comprehensive Cancer Network® (NCCN®), a not-for-profit alliance of 27 of the world's leading cancer centres devoted to patient care, research and education, is dedicated to improving the quality, effectiveness and efficiency of cancer care so that patients can live better lives.


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