Cancer is a disease of the cells, which are the body’s basic building blocks. It occurs when abnormal cells divide and multiply in an uncontrolled way.
How cancer starts
There are many types of cancer and each type develops differently. Some grow slowly, some move rapidly, and others behave unpredictably. While some types of cancer respond well to treatment, other types are more difficult to treat.
The cancer that first develops in an organ or tissue is called the primary cancer. It is considered locally advanced if the tumour is very large or the cancer has spread to nearby tissues.
How cancer spreads
If cancer cells from the primary site break away and travel through the bloodstream or lymph vessels to other parts of the body, they can grow and form another tumour at a new site. This is called a secondary cancer or metastasis. A cancer may spread to any area including the lungs, brain, liver and bones. This metastasis keeps the name of the original cancer.
For example, bowel cancer that has spread to the liver is still called metastatic bowel cancer, even though the main symptoms may be coming from the liver. A secondary cancer or metastasis is an advanced cancer.
Although medical treatments usually can’t cure advanced cancer, they may slow its growth or spread, sometimes for months or years. Palliative care can help manage cancer symptoms such as pain, and reduce side effects from cancer treatments. Other palliative care services can improve quality of life at any stage of advanced cancer.
→ READ MORE: Key questions about advanced cancer
Dr Lucy Gately, Medical Oncologist, Alfred Health and Walter and Eliza Institute for Medical Research, VIC; Dr Katherine Allsopp, Supportive and Palliative Care Specialist, Westmead Hospital, NSW; A/Prof Megan Best, The University of Notre Dame Australia and The University of Sydney, NSW; Dr Keiron Bradley, Palliative Care Consultant, Medical Director Palliative Care Program, Bethesda Health Care, WA; Craig Brewer, Consumer; Emeritus Professor Phyllis Butow, Psychologist, The University of Sydney and Chris O’Brien Lifehouse, NSW; Louise Durham, Palliative Care Nurse Practitioner Outpatients, Princess Alexandra Hospital, Metro South Palliative Care, QLD; Dr Roya Merie, Radiation Oncologist, ICON Cancer Centre, Concord, NSW; Penny Neller, Project Coordinator, National Palliative Care Projects, Australian Centre for Health Law Research, Queensland University of Technology, QLD; Caitriona Nienaber, 13 11 20 Consultant, Cancer Council WA; Xanthe Sansome, Program Director, Advance Care Planning Australia, VIC; Sparke Helmore Lawyers; Peter Spolc, Consumer.
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Cancer information
What is cancer?
How cancer starts and spreads
Dealing with the diagnosis
Common reactions to a cancer diagnosis and how to find hope