Monday, 3 August 2009
Ovarian cancer early warning hope as 'killer' gene discovered
Scientists have pinpointed a common genetic flaw behind ovarian cancer - raising hopes of earlier diagnosis of the devastating condition.
The deadliest gynaecological cancer, ovarian cancer affects almost 7,000 British women a year - and kills two-thirds.
It is dubbed 'the silent killer' because it is symptomless in the early stages and so not usually diagnosed until it is too late.
Unlocking its secrets could lead to a genetic test that would allow doctors to identify those most at risk.
These women could then be screened regularly for signs of the disease, allowing it to be picked up early when it is most treatable.
Researcher Simon Gayther said: 'I have no doubt this disease will be solved. But the sooner it is solved the better because year on year women are dying from it.'
Dr Gayther, of University College London, was part of an international team of scientists that trawled the DNA of more than 4,000 British women, including 1,800 with ovarian cancer.
This highlighted a widespread flaw that raises the risk of the disease.
Analysis of samples from another 17,000 women from around the world confirmed its importance, the journal Nature Genetics reports.
The 15 per cent of women carrying two copies of the flaw are 40 per cent more likely to develop the cancer than those with 'normal' DNA'.
This means their risk of developing the disease in their lifetime is 14 in 1,000 - compared with 10 in 1,000.
For the 40 per cent with one copy, the risk of ovarian cancer is increased by 20 per cent, to 12 in 1,000.
Dr Gayther said: 'The human DNA blueprint contains more than 10 million genetic variants.
'These are part and parcel of our characteristics and make-up - but a handful will also increase the chances of some women getting ovarian cancer and we have found the first one of these.
'There is now a genuine hope that as we find more, we can start to identify the women at greatest risk and this could help doctors to diagnose the disease earlier when treatment has a better chance of being successful.
'If you fast-forward a few years until we have identified all the risk factors for ovarian cancer, you can see a time when it might be possible to screen large populations of women to find those at greatest risk of getting the disease.
'They could then be entered into a national screening programme that could pick up their cancer earlier.
'Little has improved in ovarian cancer over the last 40 years.
'Seventy per cent of women won't survive five years after diagnosis. In that way it is a much more tragic disease than breast cancer, where survival rates are really good now compared with 20 years ago.
'There is a need for some kind of scientific breakthrough to improve the chances of women.'
Lead author Professor Dr Paul Pharoah, a Cancer Research UK senior research fellow at the University of Cambridge, said the 'hunt was on' to find the other rogue genes.
David Lammy, the MP for Tottenham and minister for higher education, lost his mother Rose to ovarian cancer last year. Her DNA was included in the study.
Mr Lammy said: 'I am pleased that Mum’s sample was included in this study as it is one step towards earlier diagnosis of ovarian cancer when treatment is more successful.
'I know in my mum's case ovarian cancer was diagnosed at an advanced stage - she had a tumour the size of a grapefruit by the time she was diagnosed - and we were all amazed that it went undetected for so long.
'Results like this show there is hope for a future where women will be diagnosed earlier and lives saved.'
The study was part funded by Cancer Research UK and ovarian cancer charity the Eve Appeal.