A new urine test designed to distinguish between benign and aggressive forms of prostate cancer may prove to be a helpful tool for doctors, as it might detect one of the common types of cancer in men.

The test is based on the idea that doctors need to know if prostate cancer is aggressive or not. “We end up over-treating our patients because physicians don't know which tumors will be slow-growing. With this research, we have identified a potential marker for the aggressive tumors,” explained lead researcher Professor Arul Chinnaiyan, from the University of Michigan Medical School.

The study, published in the journal Nature, says that a small group of molecules which are produced by the body may be linked to the aggressive form of prostate cancer. A compound called sarcosine may distinguish slow-growing prostate cancers from those likely to spread and become lethal, according to the study.

When exposed to sarcosine, benign prostate cancer cells become aggressive and turn into invasive cancer cells. Aggressive prostate cancer cells treated with sarcosine become much less invasive. “We have tantalizing evidence that this sarcosine pathway may be involved in the pathogenesis of prostate cancer,” said study leader Arul M. Chinnaiyan, MD, PhD., professor of pathology and urology at University of Michigan, Ann Arbor.

There are two types of prostate cancer: aggressive and non-aggressive. Usually, men with non-aggressive forms of prostate cancer can have a healthy life, but those with aggressive prostate cancer (who make up 1/3 of total cases) regularly don’t live more than a year and a half. At the same time, some forms of prostate cancer are slow-growing, while others tend to spread to other organs and therefore require immediate intervention.

The test would be quite useful as men diagnosed with early stage prostate cancer typically don’t have symptoms of the disease. Advanced forms of prostate cancer may have symptoms such as alterations in urinary habits, bone pain, or blood in the urine.

Studies note that common tests, such as Prostate-Specific Antigen (PSA) or digital rectal examination (DRE) are not 100% accurate in revealing the presence of prostate cancer. The method of prostate cancer biopsy is considered more accurate. Could these simple urine tests replace one day the biopsies? Researchers are confident that this method will be confirmed and validated in larger studies and will lead to the development of an easier test for prostate cancer. The researchers estimate the urine test could be available in three to five years.

Researchers not involved in the study called the findings “interesting.” The discovery could lead to new ways of preventing the spread of tumours and to better treatments, said Dr. Arul M. Chinnaiyan.

According to the estimates of the American Cancer Society (ACS), about 186,000 men will be diagnosed with prostate cancer by the end of this year.