Researchers say the test can also help determine what type of treatment men should get after diagnosis.
A new urine test could help diagnose aggressive prostate cancer and determine if men with the disease need treatment sooner rather than later.
The test has the potential to prevent unnecessary, invasive follow-up procedures as well, experts say.
The solution, called the Prostate Urine Risk (PUR) test, was created by researchers at the University of East Anglia and the Norfolk and Norwich University Hospital, both in England.
Researchers say the PUR test can detect prostate cancer and help determine which men are up to eight times less likely to need treatment within five years of diagnosis.
The research team used machine learning to assess gene expression in urine samples collected from 537 men.
When they looked at the cell-free expression of 167 genes in urine samples, they found a mathematical combination of 35 different genes that could be used to produce the PUR risk signatures.
The new test uses four PUR signatures to assess noncancerous tissue and risk groups, which lets doctors know if a person is at low-, intermediate-, or high-risk.
The PUR test measures the expression of approximately 30 genes in urine and gauges the rate at which certain functional units in the cell are being produced.
From there, the tests create a score. If this score is high, the man will need treatment sooner. If it’s low, the man will need treatment later, or might not need treatment at all, explained Daniel Brewer, PhD, a senior lecturer at the University of East Anglia and one of the study’s researchers.
Doctors have challenges when it comes to classifying which tumors will become more aggressive.
This makes it more difficult to determine appropriate treatments.
To detect prostate cancer, doctors commonly use the prostate-specific antigen (PSA) blood test or a physical test known as a digital rectal examination, a magnetic resonance imaging (MRI) scan, or a biopsy.
The PSA test is the standard assessment, but about 75 percent of men with an elevated PSA level wind up having biopsies but no cancer, the researchers noted in their study.
The other 15 percent of men who don’t have elevated PSA have prostate cancer — and 15 percent of those cancers are aggressive, the researchers added.
An ideal PUR test candidate would be any man who shows symptoms of prostate cancer such as a raised PSA, or any man who’s on active surveillance for prostate cancer, Brewer told Healthline.
Brewer said there are other urine tests used to diagnose prostate cancer, but none are widespread in clinical use.
“Our current test matches the best performance of other tests in picking up those patients that have clinically significant disease,” he said.
These men need surgery, radiotherapy, or hormone therapy.
When a man is put into the active surveillance category, it can require invasive follow up.
Active surveillance can involve taking a PSA blood test every three months and then having an MRI or biopsy every two years.
The status is also a constant reminder that the person has cancer but his future is uncertain.
About 50 percent of men who partake in active surveillance wind up treating the cancer, even if it doesn’t require treatment, researchers noted.
“We currently lack the ability to tell which men diagnosed with prostate cancer will need radical treatment and which men will not,” Shea Connell, PhD, a researcher and associate tutor at Norwich Medical School and the study’s lead author, said in a statement.
“It’s clear that there is a considerable need for additional, more accurate tests,” Connell said.
“The PUR test means we could predict whether or not men with prostate cancer already on active surveillance would require treatment.” said Jeremy Clark, a senior research associate at Norwich Medical School who was also part of the study.
Eric Klein, MD, a urologist with the Cleveland Clinic in Ohio, told Healthline that the test sounds promising. It’s not clear, however, if this test has a better sensitivity or specificity than tests currently on the market.
“It would require validation on an independent cohort of patients before it could be used clinically,” Dr. Klein said.
The research team plans to confirm the findings in another dataset and perform a multi-center trial before bringing the test to the market, Brewer said.
“If validated, this discovery could have a huge effect on those men who might have prostate cancer,” Brewer added. “I hope people will be given hope that the tricky problem of determining the correct course of treatment or no treatment in prostate cancer is on the way to being solved, and that this could be done in a noninvasive way using a simple urine test.”
Joseph L. Glajch, PhD, a consultant to the chemical and pharmaceutical industries from New Hampshire who’s been treated for prostate cancer, said previous breakthroughs in cancer urine tests have been important, but long-term survival continues to be an issue that takes years to properly assess.
The PUR test has the chance to change the face of prostate cancer and treatment, but more research is needed to see if it contributes to a significant improvement, he said.
“I think there’s a high bar for a new test to stand out from the crowd,” said Ruth Etzioni, PhD, a researcher at Fred Hutchinson Cancer Research Center in Seattle.
“It’s important for the test to address the outcomes that matter, which are mortality, overdiagnosis, and metastasis, not just diagnostic performance,” she added.