Biopsy techniques have made PSA test less useful, data show

PSA levels typically have correlated with prostate biopsy results in the detection of prostate cancer, but that correlation no longer exists for men with a normal prostate exam, suggest results of a study published online in Cancer. The study suggests that improved biopsy techniques make PSA less useful in prostate cancer screening.

Researchers at the New York Presbyterian Hospital, Weill Medical College of Cornell University, New York, performed a retrospective analysis of all prostate biopsies performed at their institution between 1993 and 2005.

Of 1,607 biopsies performed, the percentage of positive biopsies and patient ages did not change significantly over time; however, there was a significant decrease in the median PSA level in patients undergoing biopsy and an increase in the median number of samples taken at the time of biopsy. In addition, fewer biopsies were performed on the basis of a suspicious digital rectal exam, and the percentage of patients undergoing biopsy for PSA readings between 2.5 and 3.99 ng/mL increased.

The positive biopsy rate in men with PSA levels in the 2.0 ng/mL to 3.99 ng/mL range equaled or surpassed that for patients with higher PSA readings.

“The correlation between PSA and positive biopsy rate no longer holds true in our patient population for men with a normal digital rectal exam and PSA >2.0 ng/mL,” according to lead author Douglas Scherr, MD.

The authors urged development of new blood or urinary markers to better determine who needs a prostate biopsy.