In the most significant update to ovarian cancer testing guidance in 15 years, NICE now recommends changes to how the CA125 blood test is used because research shows it is less accurate for women 39 and under.
CA125 is the blood test which is commonly used in primary care to help identify possible ovarian cancer.
The changes are:
- Replacing the current single CA125 threshold of 35 U/ml with age-adjusted thresholds for women aged 40 and over, which will allow doctors to interpret results more accurately.
- For women 39 and under the guideline now recommends that CA125 should not be used on its own, because the test is not accurate enough for this age group and that direct access to ultrasound should be considered. This change moves practice closer to the dual testing approach that Target Ovarian Cancer has been calling for, where CA125 and ultrasound are used together for all age groups.
Why has this change been made?
The update is based on research conducted by Dr Garth Funston, practicing GP and Clinical Senior Lecturer in Primary Care Cancer Research at the Wolfson Institute of Population Health. His team has undertaken extensive research into the use of CA125.
Dr Funston said:
Our research using data from hundreds of thousands of women in England shows that CA125 performs differently across age groups, with the single threshold potentially missing cancers in older women while leading to unnecessary investigations in younger women. I’m pleased to see NICE have updated the guidelines and recommended age-adjusted CA125 thresholds.
Will this improve diagnosis?
Earlier and faster diagnosis of ovarian cancer can significantly improve outcomes.
Target Ovarian Cancer has long campaigned for dual testing, where the CA125 blood test and an ultrasound scan are carried out at the same time to mitigate the risk of CA125 alone not being accurate enough.
The updated NICE guidance is a step towards this approach. Recommending that CA125 should not be used on its own for women 39 and under moves practice closer to the dual testing model Target Ovarian Cancer has been calling for. The introduction of age-adjusted thresholds for women over 40 may also help improve diagnosis.
We know that the earlier ovarian cancer is diagnosed, the better the chances of successful treatment. That’s why the update to NICE guidelines is a positive step towards improving diagnosis. We welcome the recognition that CA125 should not be used in isolation for women 39 and under, but we need to see the same approach for all women, with CA125 and ultrasound undertaken at the same time regardless of age. With two-thirds of women currently diagnosed at a late stage, we urgently need further progress to change outcomes.
Where will this apply?
NICE guidance applies to England, Wales and Northern Ireland. Scotland has a different process for developing guidelines and dual testing is already available as standard.
What’s next?
Over the coming days we will be sharing more insights from Dr Garth Funston about the research behind the guideline changes.
Target Ovarian Cancer will also continue our sector-leading work to improve diagnosis by working with GPs, researchers and healthcare professionals to ensure women receive the tests they need as early as possible.
We will continue to campaign for further improvements in diagnosis, including wider adoption of dual testing.
Sign up to our campaigns network to stay informed and get involved.
