Prostate cancer urine test

4^th August 2011 - Prostate cancer screening biopsies can be painful and give inconclusive results, but now a painless urine test could help predict when high prostate-specific antigen (PSA) levels suggest a   prostate cancer or a more benign condition.

A new study reports on the test which looks for a genetic flaw that’s present in about half of all cases of prostate cancer.

Prostate cancer in the UK

Last month, the Office for National Statistics reported that prostate cancer accounts for over 25% of all male cancers diagnosed in the UK in 2009. Between 2008 and 2009, the number of prostate cancer cases increased by 12% to 34,600.

The ONS says the increase may be as a result of increased detection of prostate cancers due to an increased use of the prostate-specific antigen (PSA) blood test.

However, the UK has so far decided against screening all men for prostate cancer. NHS experts say that harm from screening outweighs any benefits it might have brought.

Some men with prostate cancer do not have raised levels of PSA, and two-thirds of men with raised levels of PSA do not have prostate cancer. PSA levels can be raised by aninflamed prostate (prostatitis), or an enlarged prostate (benign prostatic hyperplasia or BPH). The PSA test cannot distinguish between men with slow-growing prostate cancer and those with a more aggressive form of the disease.

The Prostate Cancer Charity says more research is needed to find a test capable of forming the basis of a national screening programme.

Genetic mistake

The genetic mistake the test checks is where two genes come together and fuse. It doesn’t appear to occur anywhere else in the body, or even in precancerous conditions, making it a highly specific marker for the disease.

When the genes fuse, says study researcher Dr Scott Tomlins,, a pathologist at the University of Michigan Health System, in the US. He says it’s a lot like flipping a switch: "And that gene, when it’s turned on, can cause cancer."

Refining PSA test results

Raised PSA levels often lead to a biopsy being ordred, but this is not always an easy decision for patients and doctors as biopsies can cause discomfort, anxiety, and in rare cases, lead to complications like infections. Biopsies are also expensive for the NHS.

"There really aren’t very good tools to utilise to help make that decision," Tomlins says. "We wanted to see if our urine markers could be useful in that situation."

Testing for prostate cancer biomarkers

For the study, which is published in the journal Science Translational Medicine, researchers tested the urine of 1,312 men with elevated PSA levels who had gone on to have needle biopsies or surgery to remove their prostates.