The study, published online ahead of print of the April issue of Cancer, finds the correlation between prostate biopsy results and PSA levels no longer exists for men with a normal prostate exams.

The researchers performed a retrospective analysis of all prostate biopsies performed at their institution from 1993 to 2005, finding 1,607 that satisfied their criteria.

Dr. Douglas Scherr and colleagues at the New York Presbyterian Hospital of the Weill Medical College of Cornell University in New York City divided patients into three groups based on when they received their biopsies: 1993 to 1997, 1998 to 2001 and 2002 to 2005.

The researchers examined each group for the number of biopsies performed, the number of positive biopsies, patient age, most recent PSA prior to biopsy, prostate volume and number of biopsy samples taken.

The investigators found that the number of 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.