RESEARCH from the University of Adelaide has identified a new group of molecules known as biomarkers for detecting and grading prostate cancer.
Composed of small sequences of ribonucleic acid – known as microRNA – the biomarkers are found in the fluid component of semen.
The scientists believe the biomarkers could fill a gap in the current approach for diagnosing and managing this common and often fatal cancer.
"Biomarkers that can accurately detect prostate cancer at an early stage and identify aggressive tumours are urgently needed to improve patient care,” said Research Fellow Dr Luke Selth, who is leading the project.
"We are excited by the potential clinical application of microRNAs,” he added.
Screening for prostate cancer currently relies on measuring prostate specific antigen (PSA) in blood samples taken from men. But the approach has some fallbacks.
"While the PSA test is very sensitive, it is not highly specific for prostate cancer," said Dr Selth.
"This results in many unnecessary biopsies of non-malignant disease. More problematically, PSA testing has resulted in substantial over-diagnosis and over-treament of slow growing, non-lethal prostate cancers that could have been safely left alone.
For their study, Dr Selth’s study looked at biomarkers in semen of 60 men.
"The microRNAs enabled us to more accurately discriminate between patients who had cancer and those who didn't, compared with a standard PSA test," Dr Selth said.
"We also found that one specific microRNA, miR-200b, could distinguish between men with low grade and higher grade tumours. This is important because, as a potential prognostic tool, it will help to indicate the urgency and type of treatment required."
In Australia, prostate cancer accounts for approximately 30 per cent of cancers diagnosed each year, and is the second most common cause of cancer death.
The incidence of prostate cancer in men from Asian nations is rising, and complicated by the fact that disease is often not detected until it is very advanced.
The number of new prostate cancer cases diagnosed annually has been predicted to increase to 1,700,000 worldwide by 2030, possibly leading to around 500,000 deaths.
The research was published this week in the British Journal of Cancer.