Breast Cancer Overview

by | Breast Cancer, Cancer Care, Women's Health

Breast cancer

Breast cancer is the most common cancer diagnosed in Australian women (not including skin cancers). About one in 8 women will get breast cancer by the time they are 85 years old.

The good news is that with advances in treatment and diagnosis, more women are surviving breast cancer than ever before. These days, about 88 per cent of women diagnosed with breast cancer in Australia will be alive 5 years on.

The earlier breast cancer is found, the more likely it can be successfully treated. If you notice any changes to your breasts, you should see your doctor as soon as possible. Even though most breast changes are not due to cancer, it is important to check any lumps or changes.

Breast cancer symptoms: what to look for

Look for any changes in your breasts that are not normal for you. Breast cancer is usually first noticed as a lump (that may or may not be painful) anywhere in the breast or under the arm.

Symptoms can include:

  • a breast lump or lumpiness;
  • thickening or hardness in the breast;
  • an area that feels different from the rest of the breast;
  • persistent, unusual breast pain, especially if it is in only one breast;
  • changes to the size or shape of the breast;
  • nipple changes such as a change in the shape of the nipple, redness, itching, sores, crusting or recent pulling in (inversion) of the nipple;
  • discharge from the nipple; or
  • changes in the skin overlying the breast, such as scaliness, rash, puckering or dimpling of the skin (making it resemble the skin of an orange) or a change in colour (such as redness).

breast cancer

Breast cancer causes and risk factors

Although the direct cause of breast cancer is still unknown, certain risk factors can increase your chances of having the disease.

Risk factors for breast cancer include:

  • Being a woman — while it is possible for men to get breast cancer, it is 100 times more common in women.
  • Increasing age is one of the biggest risk factors for developing breast cancer. Breast cancer becomes more common after the age of 40 years.
  • Starting your periods before 12 years of age and late menopause (after the age of 55) can increase your risk of breast cancer.
  • Family history is important: if your mother, sister or daughter has had breast (or ovarian) cancer you have a higher risk of having breast cancer, especially if they had it at an early age.
  • Genetic mutations: Two genes, BRCA1 and BRCA2, have been identified which can play a part in breast cancer. Women who inherit specific mutations in either of these 2 genes have a much higher risk of getting breast cancer (and ovarian cancer).
  • Having ever had breast cancer.
  • Having been previously diagnosed with a breast condition such as atypical ductal hyperplasia, ductal carcinoma in situ (DCIS) or lobular carcinoma in situ (LCIS) can make getting breast cancer more likely.
  • Having your first child after 30 years of age, or never having given birth, slightly increases your risk of breast cancer. (Note that women who breast feed for a total of 12 months or longer have a reduced risk of breast cancer.)

Lifestyle factors that can slightly increase your risk of breast cancer:

  • Smoking.
  • Drinking alcohol, especially more than 2 standard drinks every day. The higher the alcohol consumption the greater the risk.
  • Being overweight or obese.
  • Doing little physical activity (studies have shown that brisk walking for just 1.5 to 4 hours per week reduces breast cancer risk in postmenopausal women).

Medicines, hormones and other treatments that can increase the risk of breast cancer:

  • Current use of menopausal hormone therapy (MHT), also called hormone replacement therapy (HRT). Women taking combined MHT (oestrogen plus progesterone) may have an increased risk of breast cancer, and the risk increases the longer you take combined MHT. However, once you stop taking MHT, the risk reduces over time. It’s recommended that MHT only be used in women with moderate to severe menopausal symptoms who are aware of its risks and benefits, and it should be used for the shortest time possible.
  • Taking the oral contraceptive pill slightly increases your risk of breast cancer, although the risk levels return to normal within 10 years of stopping the pill.
  • Exposure to radiation. Having had radiation treatment for cancer or other radiation exposure increases your risk of breast cancer.
  • Women who took the medicine DES (diethylstilboestrol) during pregnancy have a slightly increased risk of breast cancer. (Daughters of mothers who took DES may also have a slightly increased risk of breast cancer after the age of 40.)

Many women who have risk factors never develop breast cancer and some women with no risk factors do get breast cancer. It’s thought that a combination of genetic and environmental factors probably causes most breast cancers.

Tests and diagnosis

Visit your doctor as soon as possible if you detect changes in your breast. However, try not to worry, as breast changes are common and in most cases will not be due to breast cancer.

Your doctor will ask about the breast changes, as well as any risk factors you may have. They will perform a physical examination, including an examination of both breasts while sitting up and lying down, looking at the appearance of the breasts and nipples, and feeling for any lumps or hardness. They will also feel for any enlarged lymph nodes under your arms and in your neck.

Tests for breast cancer

Your doctor will probably recommend several tests to help work out the cause of any breast lumps or changes.

Imaging tests that can help in the diagnosis include:

  • Mammograms – breast X-rays that are usually recommended to check breast lumps in older women.
  • Breast ultrasound, which is usually recommended to check breast masses in younger women, because mammograms are not as reliable in younger women with denser breast tissue.
  • Breast MRI (magnetic resonance imaging) can be used in women with very dense breast tissue.

A biopsy may also be recommended, which involves taking a sample of tissue from the lump or abnormal area to be examined under a microscope to look for breast cancer cells.

  • Fine needle aspiration biopsy involves removing some cells from the lump through a fine needle attached to a syringe. An ultrasound may be used to guide the needle to the right spot, and the test may be done with a local anaesthetic.
  • Core biopsy involves small sample of tissue being removed with a wider needle, usually under local anaesthetic. It may be done using ultrasound, mammogram or MRI guidance.
  • Vacuum-assisted stereotactic core biopsy involves taking several tissue samples using a needle and a suction-type instrument that is inserted through a small cut in the skin.
  • Surgical biopsy removes part or all of the lump for testing. If the whole lump is removed it is called an excisional biopsy. Surgical biopsies are generally done under general anaesthetic. Sometimes a guide wire is placed in the breast before the surgery, guided by ultrasound, mammogram or MRI, to help the surgeon biopsy the correct area.

If a biopsy result is positive for breast cancer, your doctor will refer you to a breast surgeon and/or an oncologist (cancer specialist) for further tests and treatments.

Further tests on the cells from the biopsy sample can be done to find out more about the breast cancer cells and how they will behave. This can help your doctors work out the best treatment options for you and your prognosis (a prediction of the course and outcome of the cancer).

  • Hormone receptor status can show whether your breast cancer has any receptors for hormones to attach to and stimulate the cancer to grow. Your cancer will be tested to see if it has receptors for hormones such as oestrogen or progesterone, meaning that these hormones stimulate the cancer to grow. Cancers that have hormone receptors (called hormone receptor positive cancers) usually respond well to treatment with hormone therapy. You may be told that your cancer is oestrogen receptor positive (about three-quarters of breast cancers are) or progesterone receptor positive.
  • HER2 receptor status shows whether the breast cancer cells have high levels of a protein called human epidermal growth factor receptor 2 (HER2) on their surface. The HER2 protein stimulates the growth of new cancer cells. Breast cancers that are HER2 positive are usually treated with targeted therapy aimed at the HER2 protein.
  • Genomic assays are tests that can help determine whether chemotherapy will be beneficial and the risk of the cancer coming back after treatment. They do this by analysing a sample of the tumour to see how active certain genes are.
  • Grading the breast cancer cells determines how active the breast cancer cells are, and how quickly they are growing.

Breast cancer staging

Your doctors will want to work out the stage of the cancer – whether the cancer is confined to the breast, or whether it has spread.

Breast cancer can spread from the breast to other parts of the body via the lymphatic system or bloodstream. Cancer can also spread locally. Breast cancer is said to have ‘metastasised’ when it has escaped the breast tissue and has begun to grow in other areas of the body.

Imaging tests and scans, as well as blood tests, will usually be recommended to find out whether the cancer has spread from the breast.

Breast cancer treatments

There are many different treatments for breast cancer these days. Your doctors will take many factors into consideration before recommending a type of treatment, including:

  • the size and location of the cancer;
  • how quickly the cancer cells are growing;
  • whether the cancer cells are hormone receptor positive and/or HER2 receptor positive;
  • whether the cancer has spread to the lymph nodes or anywhere else in the body; and
  • your age and general health.

Treatment options include surgery, radiotherapy, hormone therapy, targeted therapy and chemotherapy. A combination of several treatments may be recommended.

Breast cancer surgery

Breast cancer surgery aims to remove the cancerous cells before they can spread to other parts of the body. Surgery for breast cancer involves either:

  • breast-conserving surgery, which involves removing some of the breast – usually the lump and an area of normal tissue surrounding it (called lumpectomy); or
  • mastectomy – removing the whole breast.

Your breast surgeon will help you to decide which type of surgery is most suitable for you.

Breast-conserving surgery

Breast-conserving surgery with removal of some lymph nodes, followed by radiotherapy of the breast, is the most common treatment used for early breast cancer, and studies have shown that for most women with early breast cancer, it has about the same cure rate as mastectomy.

Although only part of the breast is removed, breast-conserving surgery can affect the appearance of the breast, with possible changes to breast size and shape, or the position of the nipple. A special type of surgery called oncoplastic breast conserving surgery combines breast-conserving surgery with plastic surgery to preserve the appearance of the breast as much as possible. Your surgeon will be able to advise if this type of surgery may be an option for you.


Mastectomy tends to be recommended for larger tumours, large tumours in small breasts, tumours in more than one area of the breast and for women who have previously had radiotherapy to that breast. The nipple and some or all of the lymph nodes from under the arm are also usually removed during a mastectomy.

Many women who have a mastectomy choose to have a breast reconstruction carried out — this can be done at the same time as the mastectomy or later. There are many methods of breast reconstruction and not all will be suitable for every woman. A silicone or saline implant may be used, with or without a tissue expander to gradually stretch the skin so that more skin is available for the reconstruction. In women who have larger breasts, it may be possible to take tissue from the other breast. Alternatively, skin, muscle or fat from the back or abdomen may be used for breast reconstruction. In some cases, the nipple and some of the skin overlying the breast can be conserved and used in breast reconstruction.

Women who don’t have breast reconstruction surgery can wear a breast prosthesis in their bra.

Lymph node removal

Breast cancer surgery usually involves removal of some or all of the lymph nodes in the armpit on the affected side, to detect and remove any cancer cells that may have spread to the lymph nodes. This is because breast cancer that spreads to the lymph nodes under your arm may spread to other parts of your body.

During breast cancer surgery, a sentinel node biopsy may be done, where special tests are used to work out which lymph node(s) the cancer would most likely first spread to first – the sentinel node. This lymph node is then removed and tested to see if it contains any breast cancer cells.

If no cancer cells are found in the sentinel node, there is very little chance that any of the other lymph nodes contain cancer, so no other nodes need to be removed. If the sentinel node does contain cancer cells, the surgeon will recommend removing additional lymph nodes from under your arm.

Knowing whether the cancer has spread to the lymph nodes helps determine the risk of spread to other parts of the body and if any further treatment (e.g. chemotherapy or radiotherapy) will be beneficial.

Lymphoedema (swelling of the arm) is a possible side effect of removing lymph nodes in the armpit. The risk is increased if you also have radiotherapy to the armpit.

Radiotherapy for breast cancer

Radiotherapy involves using high-dose radiation to kill the breast cancer cells. Radiotherapy to the whole breast following breast-conserving surgery has been shown to reduce the risk of the cancer coming back in the same breast. Radiotherapy is also sometimes recommended after mastectomy in cases where there is an increased risk of recurrence.

Radiotherapy for early breast cancer is usually given over about 4-6 weeks. You may find that you become tired during the treatment period and in the second half of treatment the breast skin may look like it is sunburnt. Radiotherapy to the breast doesn’t cause the hair on your head to fall out.

Breast cancer hormone therapy

Hormone therapy may be recommended following breast cancer surgery if your tumour is found to be hormone-receptor positive. Hormone therapy helps stop the growth of hormone-receptor positive breast cancer cells by blocking the action of the hormones oestrogen and progesterone, so they can no longer help the cancer grow.

The type of treatment recommended will depend on your age, whether you have been through menopause and the type of breast cancer you have.

  • Tamoxifen (e.g. Nolvadex-D, Genox) can be used in pre- and post-menopausal women and also in men with breast cancer. This medicine blocks the effect of oestrogen on cancer cells.
  • Aromatase inhibitors can be used in postmenopausal women to reduce the amount of oestrogen produced by the body. Examples include anastrozole (brand name Arimidex), exemestane (Aromasin) and letrozole (brand name Femara).
  • Ovarian treatments can be used in premenopausal women. A hormone implant called goserelin (brand name Zoladex) can be used to temporarily suppresses the production of oestrogen. Permanent treatments involve surgery to remove the ovaries or radiation to the ovaries.

Chemotherapy for breast cancer

Chemotherapy may be used to kill breast cancer cells or slow down their growth. Chemotherapy may be recommended before or after breast cancer surgery. Chemotherapy for early breast cancer is generally given for 3 to 6 months.

There are many different types of chemotherapy. Combinations of chemotherapy drugs are given to get the best cancer killing effect with the fewest side effects. Specific combinations depend on the type of cancer you have and whether it has spread. Chemotherapy drugs commonly used for breast cancer include doxorubicin, cyclophosphamide, fluorouracil, docetaxel and paclitaxel.

Common side effects of chemotherapy include:

  • temporary hair loss (depending on the drugs used, wearing a cold cap – a head cap that is connected to a cooling system – may help prevent total hair loss from the scalp);
  • nausea and vomiting (for which you can be given medicines to help control); and
  • tiredness.

Chemotherapy can also induce early menopause.

Targeted therapy for breast cancer

Targeted therapy is generally used for breast cancers that are HER2 positive.

A medicine called trastuzumab (brand name Herceptin) targets the HER2 protein, attaching to the HER2-positive cancer cells and killing them or stopping them from growing and dividing. Trastuzumab also stimulates the immune system to destroy the cancer cells.

Treatment with trastuzumab may last up to a year. Doses are usually given once every 3 weeks, and are given via a drip or by injection. Targeted therapy is used in addition to other breast cancer treatments, and often in combination with chemotherapy.

Breast cancer support groups

Breast cancer support groups allow people to talk about their experiences and support each other. Being able to reach out to others who know exactly what you’re going through is often very helpful. Support groups are a place where you can share information and express your fears in a supportive environment.

Breast cancer prevention

While there are ways to reduce your risk of breast cancer, including changing any lifestyle factors which can increase your risk, there is no absolute measure to prevent breast cancer. However, early detection can help prevent invasive breast cancer and saves the lives of many women.

For most women, being breast aware and having regular screening tests for breast cancer (see below) are the best ways to detect breast cancer at an early, curable stage.

Breast awareness

One of the most important things you can do is be breast aware – know how your breasts usually look and feel, and check regularly for lumps or changes.

See your doctor as soon as possible if you notice any changes – early detection of breast cancer improves the chances of successful treatment and recovery.

Screening mammograms

Screening mammograms can detect breast cancers before they have caused any symptoms. Mammograms use low-level X-rays to detect abnormal areas in the breast.

BreastScreen Australia recommends 2-yearly mammograms for women aged 50-74 who are at low risk of breast cancer and have no symptoms. BreastScreen Australia provides free screening mammograms to all women aged over 40 years. You do not need a referral from your doctor to have a free screening mammogram through BreastScreen Australia.

Regular screening mammograms may be recommended for some women aged 40-49 years (usually in addition to breast ultrasound) and some women aged 75 and older – talk to your doctor about whether this applies to you.

Breast tissue in women before menopause is dense, making mammograms difficult to read, so women younger than 40 do not usually have regular screening mammograms. The benefits of screening mammograms have not been shown to outweigh the risks for men.

Preventing breast cancer in women at high risk

Magnetic resonance imaging (MRI) and ultrasound scans can be used for breast screening in women who are at high risk of breast cancer because of their family history or a genetic mutation (e.g. in the BRCA1 or BRCA2 genes). Your doctor can advise you on whether you may benefit from extra screening tests.

If you are at very high risk of breast cancer, for example because of inherited factors, you may wish to talk to your doctor about preventive medicines or surgery. Having both breasts removed reduces the risk of developing breast cancer by 90 per cent or more. Taking medicines that block the effect of oestrogen in the body is another way that women at very high risk of breast cancer can reduce their risk.

Talk to your doctor about your breast cancer risk, the benefits and risks of screening, and the age that is appropriate for you to start having screening tests. And remember, if you notice any changes to your breasts at any age, see your doctor as soon as possible.