What is cancer?

Cancer happens when the body’s cells grow and multiply in an uncontrolled way. These cancer cells can form tumours (lumps of tissue). They may also invade and destroy surrounding healthy tissue.

Sometimes cells grow abnormally to form tumours, but don’t spread. These are known as ‘benign’ cancers.

Some cells spread, or are capable of spreading, to surrounding areas or to other parts of the body. These cancers are called ‘malignant’. When cancer spreads to other parts of your body, it is called ‘metastasis’.

What are the types of cancer?

Cancer can affect any area of the body, but some types are more common than others.

The most common cancers in Australia are:

• breast cancer
• bowel cancer
• prostate cancer
• uterine cancer
• skin cancers, including melanoma
• lung cancer
• head and neck cancers

What are the symptoms of cancer?

Early signs of cancer include changes to your body's normal processes, which vary depending on the organ or body system affected. For example, bowel cancer may cause a change in your bowel habits and female reproductive cancers may affect your menstrual cycle.

Most changes don’t mean you have cancer. But it’s important you see your doctor so they can rule out a serious cause.

General symptoms of cancer include:

• fatigue
• unexplained weight loss
• fever

What causes cancer?

It’s not always clear why cancer develops, but there are factors that significantly increase the risk of some cancers.

Smoking is responsible for 1 in every 9 cases of cancer and 1 in every 5 deaths from cancer.

Other risk factors include:

• drinking alcohol
• eating a poor diet
• overweight and obesity
• not getting enough exercise
• being exposed to radiation, such as ultraviolet (UV) radiation from sunlight

Sometimes cancer runs in families. You can inherit genes that make you more likely to get cancer.

In other cases, cancer is associated with an infection. For example, cervical cancer is associated with some types of human papillomavirus (HPV) infection.

Being exposed to some chemicals and dust can also increase your risk of developing some cancers.

When should I see my doctor?

There is a much greater chance of successfully treating cancer if it is found early. If you notice any worrying changes or symptoms, especially if they persist for a while, see your doctor.

How is cancer diagnosed?

Many cancers grow slowly and don’t cause symptoms for months or years.

Some cancers are found during routine tests or cancer screening tests. Accurately diagnosing cancer can take time.

Different tests are used to diagnose cancer. These depend on the type of cancer and your general health. Tests may include:

• blood tests
• imaging tests such as x-rays, CT scans, MRI scans or ultrasounds
• endoscopy

If cancer is suspected, your doctor may take a biopsy — a small sample of tissue that is examined in the laboratory. Biopsy results can give information about the type of cancer and help guide treatment.

How is cancer treated?

There are many ways to treat cancer and treatments are improving all the time. Your doctor will discuss treatment options based on the type of cancer, its stage and many other factors.

Treatment options include:

• chemotherapy — cancer-killing medicines
• radiotherapy — the controlled use of high energy X-rays to kill cancer cells
• surgery — to remove the cancer
• immunotherapy — medicines that trigger your immune system to fight the cancer
• targeted therapy — medicine designed to target the cancer and avoid other cells in your body
• hormone therapy — medicines that use hormones to stop or slow the cancer’s growth and spread
• stem cell transplant — also called a bone marrow transplant, used to treat some blood cancers

If your cancer cannot be treated, you may be offered palliative care. This refers to treatment to enhance your quality of life.

You might want to try complementary therapies. This includes a range of therapies, such as meditation or acupuncture, that can help you cope with treatment and maintain your wellbeing.

A range of health professionals are usually involved in cancer treatment, and may include:

• your GP
• oncologists (cancer doctor)
• radiologists
• surgeons
• pathologists
• oncology nurses

You might be invited to take part in a clinical trial. This is a way of testing new treatments. Clinical trials may give you access to treatments that aren’t usually available in Australia.

You can find out more about clinical trials and whether there is one available to test treatment for your cancer at the Australian Clinical Trials website.

What are the costs of cancer treatment?

Living with a long-term illness can be expensive. The cost of cancer treatment depends on different factors, such as:

• whether you are treated in a public or private hospital
• whether you continue to work or take time off from work
• if you need to travel to receive treatment
• if you have private health insurance

Some cancer treatment costs are covered by Medicare or the Pharmaceutical Benefits Scheme.

If you are unable to work due to treatment, you can apply for the Jobseeker payment from Services Australia.

Can cancer be prevented?

It is known that 1 in 3 cancers could be prevented by living a healthy lifestyle. The best ways to prevent cancer are to:

• quit smoking
• reduce your alcohol intake
• maintain a healthy weight
• eat a balanced diet
• get enough exercise
• protect yourself from the sun

You can also get checked regularly for some cancers. There are free screening programs available for breast cancer, cervical cancer and bowel cancer.

You can check your risk of cancer by using Cancer Australia’s online risk assessment tools.

What are the complications of cancer treatments?

Cancer treatments can cause side effects including:

• pain
• fatigue
• hair loss
• fertility problems
• anaemia
• constipation

Your doctor will advise you about side effects you may experience with your treatment. They can also help you manage the side effects.

Chemotherapy, bone marrow transplantation and radiotherapy increase your risk of having a second cancer. Your doctor will discuss with you the risks and benefits of any treatment offered.

Following a healthy lifestyle can also help to protect you from developing another cancer.

Resources and support

Many people diagnosed with cancer initially feel shocked, sad, angry or worried.

There is plenty of support for you. The Cancer Council can give you advice on how to tell other people, including children.

Rare Cancers Australia has information about rare cancers. This includes specialised cancer services, support services and clinical trials.

Patient organisations have local groups where you can meet other people who have been diagnosed with cancer and are having treatment.

Your doctor or specialist can answer your questions and address your concerns. You may also find it helpful to talk to a trained counsellor, psychologist or call a specialist helpline. If you are struggling or feeling overwhelmed, talk to your doctor, who will be able to provide advice and support.