Cancer screening

What is cancer screening?

Cancer screening programs look for early signs of the disease or indications that a person is more likely to develop cancer because of their age, gender or other risk factors.

In most cases, early detection of cancer increases the chances of successful treatment. In some cases, screening can lead to preventing cancer altogether.

It’s important to remember that a screening test cannot diagnose cancer. Diagnosing cancer requires further investigations to confirm the findings of a screening test.

Types of cancer screening programs

There are 3 different approaches to screening:

• Population-based screening – an entire target population is tested. For example, all people between age 45 and 74 are offered screening for bowel cancer.
• Targeted risk screening – screening of selected groups of people in high-risk categories. For example, genetic screening of people with a strong family history of breast cancer.
• Opportunistic screening – screening tests offered to people being examined for other reasons as part of a routine medical check-up. For example, a GP orders blood tests when a patient presents for a flu shot.

Developing a cancer screening test

Population-based cancer screening programs are only introduced when a range of factors can be met. These include:

• The cancer is common, with a high rate of morbidity (illness) and mortality (death).
• The test can detect the cancer in its early stages or pick up signs that the cancer may develop later.
• There is treatment available for the cancer, and the treatment is more effective, affordable, safe or acceptable in its earlier stages.
• The screening test is acceptable to people getting asked to screen since people tend to avoid unpleasant or painful medical tests, especially if they don’t have any symptoms.
• The screening program, including follow-up testing and treatment, is available to the majority of the people in the target population.
• The benefit of screening outweighs the risk in the target population.
• The target population can be contacted from records kept in a central register to undergo screening, for example, by letters sent in the mail.
• The program is cost-effective.

These strict requirements mean that population-based screening tests exist for only 3 types of cancer so far – breast, cervical and bowel. However, medical researchers are devising and trialling screening tests for other types of cancer.

New types of screening for other cancers may be available in the future.

Population-based cancer screening in Australia

There are 3 national population-based screening programs in Australia. The are for breast, bowel and cervical cancer.

Each program aims to detect pre-cancerous abnormalities or early-stage cancers before symptoms occur when there is the best chance of successful treatment and survival.

All Australians within a target population are invited to screen through these programs.

Breast cancer

BreastScreen Victoria aims to reduce deaths from breast cancer through early detection. It invites women and some trans and gender diverse people aged 50 to 74 for free 2 yearly mammography screening at a BreastScreen Victoria clinic. Women aged 40 to 49 and women aged over 74 are also eligible and can contact BreastScreen Victoria to arrange an appointment.

Find more information on breast cancer screening and breast cancer.

Bowel cancer

The National Bowel Cancer Screening Program (NBCSP) aims to reduce deaths from bowel cancer through early detection. Free bowel cancer screening is available to people aged 45 to 74. The NBCSP automatically sends free bowel screening kits to people aged 50 to 74 in the mail every 2 years. For those aged 45 to 49, you can request your first free bowl screening kit to be mailed to you. These tests can be completed at home and sent for testing via the post.

Find more information on bowel cancer screening and bowel cancer or visit the National Bowel Cancer Screening Program website.

Cervical cancer

The National Cervical Screening Program aims to prevent cancer by detecting pre-cancerous abnormalities and reduce death by early detection of cervical cancer.

Women and people with a cervix aged 25 to 74, who have ever been sexually active, should have a cervical screening test every 5 years. This test can be booked with your local GP or healthcare provider.

Find more information on cervical screening and cervical cancer or visit the National Cervical Screening Program website.

Challenges of cancer screening programs

Cancer screening has dramatically reduced illness and death from cancer in Australia. For example, since the National Cervical Screening Program was introduced in 1991, the death rate from cervical cancer has approximately halved and is now among the lowest in the world.

Despite the importance of screening, there are some challenges to overcome when trying to test large numbers of people in a population-based program, including:

Acceptability of testing

• Some people may find screening tests invasive, uncomfortable, unpleasant or embarrassing, and may not want to participate in the program. The screening programs are always looking for new ways to make screening tests more acceptable; for example, by introducing self-testing for cervical screening.
• A person may fear medical tests or procedures, and avoid screening altogether. Concerns or fears about a screening test can be discussed with a healthcare provider. Taking a family member or friend along for support and reassurance may be helpful.

Risks of screening

Screening tests aren’t perfect and have a very small chance of causing harm in the following ways:

• False negatives – this means that the test shows the person doesn’t have cancer when in fact they do.
• False positives – this means that the test results show the person has cancer when they don’t. This can lead to unnecessary worry and invasive tests such as a biopsy.
• Physical and psychological harms – some screening tests carry a small risk of side effects or complications.
• Over-diagnosis – the diagnosis of a disease that will never have caused symptoms or death during the person’s lifetime.

Due to the risks it’s important to only screen when eligible and due for screening or otherwise advised to screen by a doctor.

See your doctor if you have symptoms

Cancer screening is only for people who have no symptoms. If you have any concerns, or worrying symptoms, always see your doctor without delay.

Reducing cancer risk

You can reduce your risk of cancer by:

• having regular screening tests when due
• not smoking
• avoiding second-hand tobacco smoke (passive smoking)
• limiting your exposure to the sun and UV radiation
• being physically active
• maintaining a healthy body weight
• avoiding or limiting alcohol
• eating a healthy diet.

Where to get help

• Your GP (doctor)
• Cancer Council Victoria Tel. 13 11 20
  • Support in your own language Tel. 13 14 50
• BreastScreen Victoria Tel. 13 20 50
• National Bowel Cancer Screening Program Tel. 1800 627 701
• National Cervical Screening Program Tel. 1800 627 701
• WeCan website Email: enquiries@wecan.org.au – helps people affected by cancer find the information, resources and support services they may need following a diagnosis of cancer.