Three new studies of Prolaris, a prognostic molecular test for risk stratification in prostate cancer, were presented at the American Urological Association (AUA) Annual Meeting in Orlando, Florida.
Prolaris is a molecular diagnostic test that measures the level of RNA expression of genes involved in prostate tumor growth. This helps physicians stratify the risk of disease progression in patients with prostate cancer. Low levels of gene expression are associated with a low risk of disease progression and men in this group may be candidates for active surveillance. High levels of gene expression are associated with a higher risk of disease progression and these patients may benefit from additional therapy.
The first study followed 761 patients whose prostate cancer was diagnosed by needle biopsy and treated with conservative therapy. The primary end point was death from prostate cancer and the median follow-up time was 9.5 years. A patient’s risk of dying from prostate cancer doubled with each unit increase in the Prolaris score.
|Prolaris Test Score||<0||0-1||1.1-2||>2|
|Death Rate (%)||7||15||36||59|
The Prolaris test distinguished newly diagnosed patients who were likely to die from prostate cancer within 10 years from those with lower risk disease. The Prolaris test was a better predictor of mortality than Gleason score, prostate-specific antigen (PSA), age, clinical stage, or extent of disease.
“What clinicians need is a well-validated prognostic test that accurately predicts disease-specific mortality and can improve patient care,” said Jack Cuzick, PhD, study investigator and head of the Centre for Cancer Prevention at Queen Mary University of London, England. “With standard clinical tools like Gleason Score or PSA, we can’t adequately define prognosis. The Prolaris test is highly prognostic for disease-specific death among men being conservatively treated.”
The second study examined the rates of biochemical recurrence (BCR) in 230 men who had Gleason Scores of either 3+4 or 4+3. There was no difference in BCR based on an assessment using Gleason score alone. However, the Prolaris test outperformed upgrading to Gleason 3+4 or 4+3 in predicting which patients would experience biochemical recurrence after radical prostatectomy.
“Prolaris is rapidly becoming the leading test to assess the aggressiveness of prostate cancer and to help physicians select the most appropriate clinical management for newly diagnosed patients with prostate cancer,” said Michael Brawer, MD, vice president of Medical Affairs at Myriad Genetics, Salt Lake City, Utah.