Online advertisements promoting early detection blood testing for ovarian cancer in Australia have sparked debate about potential harms, including false positives and unnecessary medical costs. The ads, which call ovarian cancer a 'silent killer,' direct women to a website offering a test for $1,495.
Who is the test for?
BCAL Diagnostics, which runs the early detection site, said the test is designed only for people with higher risk of ovarian cancer—those with a family history, genetic risk factors or other factors flagged by their doctors. Chief executive Anne-Louise Arnett stated: 'It is not positioned as a general population screening test, a standalone diagnostic test, or a replacement for specialist clinical assessment or surveillance.'
The blood test works by extracting DNA fragments shed into the bloodstream and scanning for chemical tags and genetic patterns produced by cancer cells. Machine learning detects abnormal signals. The test has not been approved by Australia's Therapeutic Goods Administration.
Accuracy concerns
The Ovarian Cancer Research Foundation said there was limited peer-reviewed data on the test, with a 2025 study including only 42 ovarian cancer samples. The manufacturer reports a sensitivity of 78.2%, meaning it may miss ovarian cancer in about one in five people with the disease, and a specificity of 94%.
Dr Barry Kramer, an oncologist and former director of cancer prevention at the US National Cancer Institute, said a 6% error rate for specificity is significant for rare diseases like ovarian cancer. He calculated that if the test is given to 100,000 older women, it would accurately detect about 23 of the 30 expected cancer cases, but nearly 6,000 women without cancer would test positive. 'Those 5,998 women, having paid about $1,495 out-of-pocket, will now go on to further testing in the Australian healthcare system,' Kramer said, adding this could create fear, psychological distress and further medical costs.
Lack of evidence for improved outcomes
Dr Brooke Nickel from the University of Sydney's school of public health said there is 'no robust evidence which demonstrates blood-based early detection screening tests improve health outcomes, including in higher-risk groups.' She warned that terms like 'silent killer' can make rare diseases seem more common and that empowerment language suggests more testing is always beneficial, blurring trade-offs and distorting public understanding of risk.
Anita Dessaix, chair of the Cancer Council's public health committee, said early detection is vital but any test must be supported by strong evidence that benefits outweigh harms. She advised people not to ignore symptoms and to discuss concerns with their GP.
David Hunt, research and policy director of the Ovarian Cancer Research Foundation, said with a survival rate of just 49%, affected people are desperate for a solution. 'The [BCAL] test may have some value but doesn't yet meet the threshold for sensitivity and specificity.'
