Question asked by: 
Attendee at Being Together Plymouth
Date asked: 
Oct 2015
Are CA-125 levels useful in monitoring the development of the disease, and recurrence of disease?
Response by Guest experts from Being Together Plymouth

There is no national screening programme for ovarian cancer. At the moment we’re waiting for the results of the UKCTOCS trial (UK Collaborative Trial of Ovarian Cancer Screening) for which 200,000 women were identified to go into this trial. Half of those, so 100,000, had no screening at all, which is what happens now and the other half got split into having ultrasound or a CA125 test once a year. 

We think that absolute levels of CA125 is not going to give us the answer, but it’s a woman’s individual change over time. Depending on how quickly it climbs, that may be a way of detecting cancers early. The whole idea of the trial is to pick up on a woman at early stage, so that chances of cure are higher. The answer to that end point of, ‘Can we pick up a woman early enough to cure them?’ is not yet known. Women are being followed up and we think that towards the end of this year, the data will be available. 

At the moment there’s no proven, effective screening tool for ovarian cancer. UKFOCSS looked at high risk women and in that trial there were only 3,500 women, but every one of those had at least a 10 per cent chance of having ovarian cancer. We know that that trial did not work at picking up early cancers. The investigators have gone back to that and said, ‘We were screening too infrequently. Once a year’s not enough.’ Now they’re looking at screening every four months. If it doesn’t detect it in a high risk group, it’s unlikely to detect it in a low risk group, using crude tools. So the focus now is, ‘How can we get a better tool to pick up this disease earlier?’

I think the question about CA125 at follow up is a different answer. If your CA125 is elevated when you have your surgery, that’s what we call a marker, and you would expect that if the cancer occurs, it will produce CA125 again. So it’s a useful marker.