A GENETIC variant has been discovered that appears to help men develop aggressive and deadly forms of prostate cancer, researchers have found.
The discovery points towards ways of identifying men most at risk by screening their DNA.
Most men with prostate cancer have slow-growing “pussycat” forms of the disease, but some individuals develop aggressive “tiger” tumours.
Prof Jianfeng Xu, from Wake Forest University Baptist Medical Centre in North Carolina, US, who led the research, said: “The current inability to accurately distinguish risk for life-threatening, aggressive prostate cancer from the overwhelming majority of slow-growing cases creates a treatment dilemma.”
While scientists had already identified genetic variants linked to the risk of developing prostate cancer, this is the first known to be associated with disease aggressiveness.
The researchers analysed genetic information from 4,849 men with aggressive prostate cancer and 12,205 with slow-growing forms of the disease.
They discovered a DNA mutation known as rs4054823 that led to a 25 per cent higher risk of developing an aggressive tumour.
“A single variant with a moderate effect such as this is unlikely to be sufficient on its own at predicting risk, but its identification is significant because it indicates that variants predisposing men to aggressive disease exist in the genome [complete genetic code blueprint],” said Prof Xu.
“This finding addresses one of the most important clinical questions of prostate cancer – the ability at an early stage to distinguish between aggressive and slow-growing disease.
“Although the genetic marker currently has limited clinical utility, we believe it has the potential to one day be used in combination with other clinical variables and genetic markers to predict which men have aggressive prostate cancer at a stage when the disease is still curable.”
He believed that as more genetic markers emerge it may be possible for men to be tested for susceptibility to aggressive prostate cancer even before the disease makes an appearance.
“We speculate that a panel of variants could be an important part of developing a screening strategy that could reduce the number of men requiring screening, thereby reducing over-diagnosis, while also identifying men at risk for developing aggressive disease at a stage when the disease is potentially curable,” said Prof Xu.
The research is reported online today in the journal P roceedings of the National Academy of Sciences.
Every year, about 2,400 men develop prostate cancer in Ireland. About 550 men here die each year from the disease.