Doctors currently rely on blood tests and/or rectal exams to spot prostate cancer. Now, researchers, including Dr. David Crawford of the University of Colorado School of Medicine, say there's a new weapon in the arsenal for identifying cancer cases---urine exams. Gen-Probe's Progensa PCA3 test catches roughly half the prostate cancer cases in men who had abnormal prostate protein levels or digital rectal exams, according to Reuters . The tests may help prevent unnecessary damage to the walnut-shaped prostate gland, which produces semen. Biopsies are difficult, painful, and may harm healthy tissue, and can still miss tumors entirely. The new test seeks a genetic material known as PCA3, which is overactive in prostate cancer cases. A light touch of the prostate can cause the substance to be released, which can then be detected in urine. If that doesn't do the trick, the doctors may want to step aside and let a prostate cancer-sniffing dog check patients out. "The dogs are certainly recognizing the odor of a molecule that is produced by cancer cells," French researcher Jean-Nicolas Cornu, who works at Hospital Tenon in Paris, tells US News & World Report . Unfortunately, scientists do not know what the molecule is and, of course, the dogs aren't telling them.