Screening may provide early ovarian cancer warning
Preliminary results from a large UK clinical trial, part-funded by Cancer Research UK, suggest that ovarian cancer screening may help to detect the disease in its early stages.
The UK Collaborative Trial of Ovarian Cancer Screening (UKCTOCS) involves over 200,000 women between the ages of 50 and 74 years, who were recruited from 27 Primary Care Trusts (PCTs) in England, Wales and Northern Ireland between 2001 and 2005.
Of these, about 100,000 are being regularly screened, and will continue to be invited for screening until 2011, with follow-up continuing until December 2014. The other women are not being screened.
The initial results have now been analysed and the results published in the Lancet Oncology medical journal.
Preliminary results reveal that ovarian cancer or borderline tumours were detected in 87 women during the first round of screening.
Almost half (48 per cent) of the 58 cancers detected were at an early stage and therefore might not have been picked up for some time if the women had not been screened, as the early stages of ovarian cancer often do not cause any noticeable symptoms.
The first round of screening missed 13 women who subsequently went on to develop ovarian cancer within 12 months of screening.
Further analyses will provide details of cancers that develop in screened women in the remaining years of the study and at what stage they are detected.
Lead investigator Professor Ian Jacobs, director of the University College London Institute for Women's Health, noted that there is still a long way to go before scientists know whether or not screening for ovarian cancer saves lives.
He also pointed out that screening can cause anxiety and lead some people to undergo unnecessary operations. So experts must therefore balance any benefits offered by screening with these downsides.
"The UKCTOCS trial is the largest trial of its kind ever run to investigate ovarian cancer and we are enormously grateful to the women who have taken part," he continued.
"It will conclude in just over five years and if the findings are positive my hope is that what we learn will pave the way for a national ovarian cancer screening programme.
"The first results are an important step forward and the trial itself is a powerful demonstration of how our best scientists, clinical researchers and healthcare workers in the UK collaborate in research and involve volunteers nationwide to improve health."
The trial is looking at two different screening methods - a blood test that measures levels of a protein called CA125 and an ultrasound scan that looks for abnormalities in the ovaries.
The researchers reported that both methods appear to be effective at detecting the early stages of ovarian cancer.
Kate Law, Cancer Research UK's director of clinical trials, said: "These are early but encouraging results. Ovarian cancer is often referred to as the silent killer because the symptoms are common to many other diseases. Most cases are diagnosed at later stages when treatment is less successful. This clinical trial is important in developing an accurate screening test to help with early diagnosis and reduce the number of women dying from the disease."
Dr Usha Menon, trial coordinator and one of the principal investigators, described the results as "extremely encouraging".
She said: "The early results suggest that both types of screening can be used on a large scale and both successfully identify ovarian cancers.
"However, we must wait 'til 2015 before we can conclude whether or not a wider screening programme could lead to a fall in deaths due to ovarian cancer."
Menon, U., Gentry-Maharaj, A., Hallett, R., Ryan, A., Burnell, M., Sharma, A., Lewis, S., Davies, S., Philpott, S., & Lopes, A. (2009). Sensitivity and specificity of multimodal and ultrasound screening for ovarian cancer, and stage distribution of detected cancers: results of the prevalence screen of the UK Collaborative Trial of Ovarian Cancer Screening (UKCTOCS) The Lancet Oncology DOI: 10.1016/S1470-2045(09)70026-9