UK Collaborative Trial of Ovarian Cancer Screening


The mortality results of UKCTOCS, the largest ever ovarian cancer screening trial, were published in The Lancet in December 2015. In the trial women underwent one of two forms of screening (1) multimodal screening (MMS) based on a yearly CA125 blood test interpreted using the Risk of Ovarian Cancer Algorithm (ROCA) followed by an internal (transvaginal) scan and repeat blood test if the result was abnormal (2) ultrasound screening (USS) based on a yearly internal scan which was repeated if the result was abnormal. They were offered between 7-11 annual screens. The ovarian cancer outcomes till 31st December 2014 of women in the screen groups were compared to those of women in the control (C) group who were not offered any screening.

The trial showed for the first time that multimodal screening results in the detection of significantly more earlier stage ovarian/peritoneal cancers than no screening. It may be possible to prevent 1 in 5 (20%) ovarian cancer deaths if women undergo annual multimodal screening (MMS) but this needs to be confirmed on further follow up.

For every woman found to have ovarian cancer on screening, 2 additional women in the MMS group and 10 additional women in the USS arm had surgery where the ovaries were only found to have benign lesions or were normal. The surgical complication rate of these additional operations was around 3.1% (MMS) and 3.5% (USS) which matches the standard complication rate for such surgery. In addition, while screening did not raise anxiety, levels of worry were higher in women who had abnormal results and required additional 2nd line tests.  Rarely women had complications related to having a blood test or an internal scan such as pain, bruising or cystitis.

Our data at this point is not sufficient to recommend a National Screening Programme like for breast and cervical cancer. We estimate that further follow-up of approximately four years is required before we can confirm the reduction in deaths.  However, we remain hopeful that following this time period we will be able to provide the National Screening Committee with all the information they need to make a decision as to whether the NHS should have an ovarian cancer screening programme.

The UKCTOCS data provide fresh impetus to continue to pursue screening as an option for reducing mortality in this most lethal of gynaecological cancers. We are greatly indebted to our trial participants, the funding agencies and the many NHS staff who have brought us so far.

Jacobs IJ, Menon U, Ryan A. Ovarian cancer screening and mortality in the UK Collaborative Trial of Ovarian Cancer Screening (UKCTOCS): a randomised controlled trial. Lancet 2015; published online Dec 17. (Click this link to access the published scientific article).

A meeting was held at the Royal College of Obstetrics and Gynaecology to present the results. The meeting was recorded and can be viewed by clicking on the following links:-