At first, the aim of the tests is to work out whether you have primary or secondary cancer. If the tests show that the cancer is secondary, more tests will be done to try to find the primary cancer. The tests you have will depend on your health and symptoms, the location of the secondary cancer and the suspected location of the primary cancer.
If the tests find where the cancer started, the cancer is no longer an unknown primary. It will then be treated like the primary cancer type. For example, bowel cancer that has spread to the liver will be given the treatment for advanced bowel cancer.
Waiting for test results can be a stressful time. It may help to talk to a friend, family member or health professional, or call Cancer Council 13 11 20.
Tests used to find where the cancer started
| blood and urine tests | samples of your blood and urine are sent to a laboratory to be checked for abnormal cells and chemicals called tumour markers |
| biopsy | a tissue sample is taken from a secondary tumour, an enlarged lymph node or bone marrow and sent to a laboratory for examination |
| endoscopy/ colonoscopy | this procedure uses an instrument to look inside the body and take small tissue samples |
| imaging tests | X-rays; ultrasounds; and CT, PET-CT, MRI and bone scans create images of the inside of the body |
Key resource
Download a PDF booklet on this topic.
More resources
Prof Linda Mileshkin, Medical Oncologist, Clinical Researcher, Peter MacCallum Cancer Centre, VIC; Christine Bradfield, Consumer; Cindy Bryant, Consumer; Dr Maria Cigolini, Head, Department of Palliative Medicine, Royal Prince Alfred Hospital, and Clinical Lecturer, The University of Sydney, NSW; Mary Duffy, Advanced Practice Nurse and Nurse Coordinator, Lung Service, Peter MacCallum Cancer Centre, VIC; Karen Hall, 13 11 20 Consultant, Cancer Council SA; Dr Andrew Oar, Radiation Oncologist, Icon Cancer Centre, Gold Coast University Hospital, QLD; Dr Siobhan O’Neill, Medical Oncologist, Nelune Comprehensive Cancer Centre, NSW; Prof Penelope Schofield, Department of Psychological Sciences and the Iverson Health Innovation Research Institute, Swinburne University of Technology, and Head, Behavioural Science in Cancer, Peter MacCallum Cancer Centre, VIC; Frank Stoss, Consumer.
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