PSA Testing Plus Drug Therapy May Help Identify Prostate Cancer in Some Patients
AUGUST 14, 2012
Researchers at New York-Presbyterian Hospital/Weill Cornell Medical Center have devised a new approach for detecting risk of aggressive prostate cancer, while avoiding unnecessary biopsies.
As reported in a news release from Weill Cornell Medical College, investigators found that administering the 5-alpha-reductase inhibitor drugs finasteride and dutasteride to men who had a PSA score of 4 or higher, who had a normal digital rectal examination, and two or more negative biopsies made it easier to “differentiate prostate cancer from benign prostate disease in patients who are difficult to diagnose,” according to lead investigator Steven Kaplan, MD, E. Darracott Vaughan Jr., Professor of Urology at Weill Cornell Medical College and director of the Iris Cantor Men's Health Center at NewYork-Presbyterian/Weill Cornell.
The study results were published in The Journal of Urology. For the study, a total of 276 men were given 5 mg finasteride or 0.5 mg dutasteride. In phase I of the study, 97 patients “had their PSA measured at 6 and 12 months, a transrectal ultrasonography and a biopsy performed at 1 year,” according to the Weill Cornell Medical College news release. After one year, mean PSA scores for this group had decreased by 47% and mean prostate volume had decreased by almost 18%. However, “the magnitude of reduction was significantly greater in men with benign prostate disease and significantly less in the 28% of patients whose prostate biopsy detected cancer.”
For phase II, 179 men who had received 5 mg finasteride or 0.5 mg dutasteride underwent biopsy only when their PSA changed by more than 0.4 ng/ml. Twenty-seven percent of these patients met this trigger point, slightly more than half of whom (54%) were diagnosed with cancer following biopsy (77% of this group had high-grade tumors – a Gleason score 7 or greater).
These results indicate that combining drug therapy with PSA testing may help physicians identify hard-to-detect cancers in some men (by sending them for biopsy following small changes in PSA score) while helping other men avoid unnecessary biopsies.