Urine Test Detects Risk of Prostate Cancer

May 21, 2015

An elevated PSA score may mean there are cancer cells, but not always. But now, a less invasive test can help more precisely determine if that biopsy is necessary.

Prostate cancer is the most common cancer in men, outside of skin cancer. Measuring prostate specific antigen, or PSA, and sometimes a digital rectal exam are standard ways to determine if a man needs a follow-up biopsy. An elevated PSA score may mean there are cancer cells, but not always.  But now, a less invasive test can help more precisely determine if that biopsy is necessary. 

The University of Michigan Health System is using a new urine test-Mi-Prostate Score, or MiPS-to improve PSA screening. The test incorporates three specific markers that could indicate cancer which when used in conjunction with PSA screening, may be more accurate at detecting cancer.1

According to Arul Chinnaiyan, MD, PhD, and Scott Tomlins, MD, PhD, who validated the new test on nearly 2,000 urine samples, MiPS was more accurate than PSA alone for predicting cancer as well as predicting aggressive prostate cancer that is likely to grow and spread quickly. 

In 2005, Dr. Chinnaiyan discovered a genetic anomaly that is observed in about half of prostate cancers, where two genes change places and fuse together. He believes that this gene fusion, transmembrane protease serine (T2: ERG, patent pending) is a cause of prostate cancer. The new test looks for the T2: ERG fusion and another marker, prostate cancer antigen 3 (PCA3). These factors, in addition to PSA levels, measure prostate cancer risk and identify aggressive tumors.

This test is combined with serum PSA levels to produce a risk assessment for prostate cancer. The test also predicts risk for aggressive tumors, helping doctors and patients make decisions about whether to wait and monitor test levels, or pursue immediate biopsy. This is important because currently one million men will undergo a prostate biopsy this year, but only about one-fifth of those biopsies will result in a cancer diagnosis. So this noninvasive test may eliminate a lot of painful procedures and worry.

References: