16 May 2011
ByAppeared in BioNews 607
Screening for breast and prostate cancer based on genetic risk factors as well as age could reduce the number of people screened without a significant reduction in the number of cancers detected, a new study suggests.
'This is an alternative approach to the existing screening programme and might even have the potential to reduce over-diagnosis, and in turn, lower costs', said lead author Dr Nora Pashayan from the Department of Public Health and Primary Care, University of Cambridge.
Dr Pashayan and UK colleagues used a statistical model to examine the effect of offering screening to men and women based on their genetic risk factors as well as their age. They compared current screening approaches for breast and prostate cancer with the new model and found using the new model would have resulted in 24 percent (%) fewer women being screened and 14% fewer cases of breast cancer being detected. They also found 16% fewer men would be eligible for prostate cancer screening but only 3% fewer cases would be detected.
'For our model to be used women would need to have a genetic test before the age of 35', said Dr Pashayan, explaining how the approach would work in breast cancer screening. 'This would be a simple blood test to identify genetic risk and, depending on the results, the age at which they should be invited for screening could be calculated'.
Breast cancer is the most commonly diagnosed cancer in the UK. In England, each year almost 31,000 women between the ages of 35 and 79 are diagnosed with the disease. Routine screening is currently offered to all women over the age of 50. Prostate cancer is the most common cancer in men and 37,000 men are diagnosed each year in the UK. Aggressive forms of the cancer require treatment to prevent the cancer from spreading.
Using the new model could also improve the detection of more aggressive cancers by identifying those at high risk. Dr Pashayan said: 'This approach means that screening women at high risk of the disease when they are younger will pick up some cancers earlier. These cancers tend to be more aggressive so the earlier they are picked up the better'.
Professor Paul Pharaoh, one of the authors of the study, said: 'Even though our analysis is based on a theoretical model… it still shows that personalised screening has the potential to reduce the disadvantages of a screening programme without losing any of its benefits. We now need more research'.
The study was published in the British Journal of Cancer and was funded by Cancer Research UK and COGS, a project funded by the European Commission.