There is a new biotechnology that may assist with the detection of prostate cancer and the reduction of unnecessary prostate cancer biopsies along with subsequent overtreatment. Due to the discovery of specific prostate cancer DNA fusions, a new urine test for prostate cancer was developed by researchers at the University of Michigan.
Scott Tomlins, MD, PhD, a PCF Young Investigator and a team of researchers at the University of Michigan under the direction of Arul Chinnaiyan, MD, PhD, also a PCF Investigator, developed a prostate cancer–specific test involving 2 genetic biomarkers prevalent in most prostate cancers and easily identified in a simple urine test. The DNA markers include the TMPRSS2:ERG gene fusion, which occurs in 50% of prostate cancer patients, and PCA3 DNA. For 95% of patients with prostate cancers, both TMPRSS2:ERG and PCA3 DNA are expressed at elevated levels.
“With more than 300 types of human cancer, this two-gene DNA urine test is ultra-specific to prostate cancer and prostate cancer only,” observed Jonathan W. Simons, MD, president and CEO of the Prostate Cancer Foundation. “PSA in the blood is not cancer specific, but this new DNA diagnostic tool is.”
With less than half of the prostate biopsies resulting in a cancer diagnosis each year, the availability of an easy-to-use urine test designed to identify the presence of cancer has the potential to eliminate thousands of unnecessary prostate biopsies each year in the US.
Patients with low levels of TMPRSS2:ERG and PCA3 DNA markers have only a 20% chance of being diagnosed with prostate cancer. Plus, the likelihood of having a high-risk cancer is less than 10%, according to Dr Tomlins. However, patients with elevated levels of these biomarkers often have an 80% possibility of having cancer with a 50% risk of having high-grade cancer. An association also exists between test results and the corresponding size of the tumor in patients with prostate cancer.
“There is no one biomarker for every prostate cancer,” explains Dr Tomlins. “But, by combining these two specific biomarkers that are widely found in prostate cancer patients, we now have a tool for making more informed decisions. Using this combined test, patients and their physicians can now decide to proceed to biopsy or delay a biopsy with greater confidence.”
The results of studies using the new urine test were published in Science Translational Medicine.
Source: PCF.