An experimental, non-invasive biomarker test has shown promise to accurately detect prostate cancer, more than any other screening method currently in use, say researchers.
Developed at the University of Michigan, the screening method is a simple urine test that detects the presence of four different RNA molecules.
During a study, this method accurately identified 80 percent of patients who were later found to have prostate cancer. Furthermore, it was 61 percent effective in ruling out disease in other study participants, say the researchers.
According to the researchers, this test is even more accurate than the newer PCA3 test, which screens for a molecule specific to prostate cancer.
"Relative to what is out there, this is the best test so far," said the study's lead author, Arul Chinnaiyan, director of the Michigan Center for Translational Pathology at the University of Michigan.
He says that the "first generation multiplex" biomarker test may be improved with the uncovering of further molecular causes of prostate cancer.
"We want to develop a test to allow physicians to predict whether their patients have prostate cancer that is so accurate a biopsy won't be needed to rule cancer out. No test can do that now," Chinnaiyan said.
During the study, the researchers found that four biomarkers were significant predictors of prostate cancer, one of which was the PCA3 transcript expression.
When tested as individual biomarkers, three of them outperformed PSA, which had identified all of the men in the study as potentially positive for prostate cancer.
Chinnaiyan revealed that the combination of the four biomarkers achieved a specificity and positive predictive value of greater than 75 percent, which was five percent better than use of a PCA3 test alone.
The researcher said that specificity was the probability that a test would indicate a negative result if a person did not have a disease, and the positive predictive value was the proportion of patients with positive test results who were correctly diagnosed.
The study has been published in Cancer Research, a journal of the American Association for Cancer Research.