Cancer: an overview

Over 40% of new cancer cases in Australia occur in people of working age, so it is not unusual for a workplace to provide support to an employee affected by cancer. To help you create a cancer-friendly workplace, this page provides a brief introduction to what cancer is, the risk factors and current treatments.

What is cancer?

Cancer is a disease of the cells. Cells are the body’s basic building blocks – they make up tissues and organs. The body constantly makes new cells to help us grow, replace worn-out tissue and heal injuries.

Normally, cells multiply and die in an orderly way, so that each new cell replaces one lost. Sometimes, however, cells become abnormal and keep growing. In solid tumours, the abnormal cells form a mass or lump called a tumour. In some cancers, such as leukaemia, the abnormal cells build up in the blood. Not all tumours are cancer. Benign tumours tend to grow slowly and usually don’t move into other parts of the body or turn into cancer. Cancerous tumours, also known as  malignant tumours, have the potential to spread. They may invade nearby tissue, destroying normal cells. The cancer cells can break away and travel through the  bloodstream or lymph vessels to other parts of the body.

The cancer that first develops is called the primary cancer. It is considered localised cancer if it has not spread to other parts of the body. If the primary cancer cells grow and form another tumour at a new site, it is called a secondary cancer or metastasis. A metastasis keeps the name of the original cancer. For example, lung cancer that has spread to the bones is called metastatic lung cancer, even though the person may be experiencing symptoms caused by problems in the bones.

How common is cancer in Australia?

On average, one in two people will be diagnosed with cancer by the age of 85. In 2019, it’s estimated that about 145,000 new cases of cancer will be diagnosed in Australia (excluding basal and squamous cell carcinoma of the skin).

The most commonly diagnosed types of cancer are breast, prostate, bowel (colorectal), melanoma and lung. Together, these five cancers account for about 60% of all  cancers diagnosed in Australia.

Many cancers can be treated successfully, and about 70% of people diagnosed with cancer will still be alive five years after their treatment.

Cancer in the working population

In Australia, about 40% of people diagnosed with cancer are of working age (20–64).

While most people newly diagnosed are 65 years or older (58%) and may be retired, their main carer may be a younger person in paid employment.

What are the risk factors?

The causes of many cancers are not fully understood. However, several risk factors may make some people more susceptible than others. These include:

• smoking tobacco/passive smoking
• exposure to UV radiation (e.g. from sunlight)
• drinking too much alcohol
• eating too much red and processed meat
• not eating enough fruit and vegetables
• being overweight
• lack of physical activity
• chronic infections, including the human papillomavirus (HPV) and hepatitis B or C
• family history and genetic susceptibility
• hormonal factors
• exposure to hazardous substances, chemicals, dust or radiation (e.g. asbestos, uranium, coal tar, wood dust, diesel exhaust, lead, benzene).

Having a risk factor doesn’t necessarily mean that a person will get cancer. However, people who are aware of risk factors can make better lifestyle choices to reduce their risk.

How is cancer treated?

Treatment for cancer is often successful if the cancer is found early.

Most cancers are treated with surgery, chemotherapy and radiation therapy (also known as radiotherapy). Other treatments, such as hormone therapy, immunotherapy and targeted therapy, can also be used for some types of cancer.

Treatments may be used alone or in combination. Many people will have several cycles of treatment over a number of weeks or months.

Main types of cancer treatments

Surgery – An operation to remove cancerous tissue and some healthy tissue around it. It may be a major, invasive operation or a relatively minor procedure.

Drug therapies – Drugs are delivered into the bloodstream so the treatment can travel throughout the body.
This is called systemic treatment and includes:

• Chemotherapy – uses drugs known as cytotoxics to kill cancer cells or slow their growth. There are many different types of chemotherapy drugs. They are usually given  through a vein (intravenously), but some may be given as tablets, cream or injections.
• Hormone therapy – uses synthetic hormones to block the effect of the body’s natural hormones, which sometimes help cancers grow. The treatment may be given as tablets or injections.
• Immunotherapy – uses the body’s own immune system to fight cancer cells. Immunotherapy drugs are usually administered into a vein (intravenously).
• Targeted therapy – attacks specific particles (molecules) within cells that allow cancer to grow and spread. It is generally given in tablet form (orally).

Radiation therapy (radiotherapy) – Uses a controlled dose of radiation, such as x-rays or gamma rays, to kill cancer cells or damage them so they cannot grow, multiply or spread. External beam radiation therapy or internal radiation therapy (brachytherapy) may be offered.

Side effects of treatment

Many people who have treatment for cancer experience side effects. These vary depending on the treatments given. Side effects also vary from person to person, even among people having the same treatment.

Side effects can occur during or after treatment. They may be short term or last for a long time.

After a cancer diagnosis or treatment, some people are able to continue working during treatment but may need some time off for treatment and recovery. As treatments have improved, more people are able to keep working throughout treatment with the support of their employers. The work environment may help some people keep their lives as normal as possible. Cancer or the treatment side effects may mean that some people need to stop working.