New Urine Tests Could Eliminate the Need for Prostate Biopsies

Studies show that a new urine test could eliminate the harmful effects of over-diagnosis and over-treatment of prostate cancer.

Although prostate cancer is the most common cancer in men, some doctors suggest that the current screening process may be more detrimental, as well as ineffective, than helpful. In 2007, over 200,000 men in the United States were diagnosed with prostate cancer, while over 29,000 men died from the disease.

Researchers are hopeful that urine tests that detect two genetic markers associated with prostate cancer will provide more accurate diagnoses. According to a study published in Science Translational Medicine, an excess of Prostate Cancer Antigen-3 (PCA-3) occurs in about 95 percent of prostate tumors. In addition, a fusion gene called TMPRSS2-ERG is present in roughly half of all prostate cancers. Therefore, a urine test to detect these genetic markers would provide a more effective purpose for men to go through the discomfort of a prostate biopsy.

Current screening procedures include a blood test that measures the level of prostate-specific antigen (PSA) in men, which often leads to false positives and unnecessary biopsies. Although it may seem like a great idea to be more safe than sorry, unnecessary biopsies as well as further treatment put men at high risk for harmful side effects such as incontinence, impotence, radiation exposure, and avoidable expenses.

Lead researcher Dr. Scott Tomlins and his team studied urine samples from 1,312 men who had high levels of PSA after initial blood tests. Based on tests from those samples, the men were placed into three groups: low, intermediate, and high-risk for prostate cancer. These predictions were eventually compared to results from their prostate biopsies. Researchers found that 21 percent of men from the low-risk group, 43 percent from the intermediate-risk group, and 69 percent from the high-risk group actually had prostate cancer. Furthermore, 7 percent of those diagnosed with prostate cancer from the low-risk group had aggressive prostate cancer, compared to 40 percent from the high-risk group.

So far, results seem promising. On the other hand, further testing will have to look at a more diverse sample of men. Most of the men from this study are Caucasian. In addition, researchers will be testing patients who have not already had initial PSA tests in order to determine how effective urine tests could actually be.

Studies have shown that prostate cancer is indeed curable in its early stages. Therefore, regular screening would seem to be beneficial to men, especially in their high-risk, later years. At this point, some doctors argue that current procedures have not proven to be as beneficial as we might imagine. Further studies of this new urine test could eventually turn those results around.