Evidence suggesting PSA cutpoint of 2.5 ng/mL for prompting prostate biopsy: review of 36,316 biopsies.

OBJECTIVES

To determine whether a prostate-specific antigen (PSA) level of 2.0, 2.5, or 4.0 ng/mL is the most appropriate cutpoint for determining the need for prostate biopsy. It has been suggested that the PSA cutpoint of 4.0 ng/mL is inappropriate because the rate of prostate cancer detection is similar in patients with lower PSA values. Some investigators have recommended a 2.6-ng/mL cutpoint. Others have recommended a cutpoint of 2.0 ng/mL.

METHODS

A total of 36,316 prostate biopsies submitted to DIANON Systems from January 1, 1997 through December 31, 2001 were reviewed. These biopsy specimens also had DIANON PSA test results available that had been performed within 6 months of the biopsy date. These biopsies were stratified according to the PSA level within the 6 months before the time of biopsy, and the prostate cancer detection rate was determined for the stratified PSA levels.

RESULTS

The detection rate of prostate cancer varied according to the PSA level. The incidence of prostate cancer was similar for the groups with less than 2.0 ng/mL and 2.0 to 2.5 ng/mL (18.67% and 21.89%, respectively). Also, the groups with 2.5 to 4.0 ng/mL and 4.0 to 10.0 ng/mL had similar cancer detection rates (27.48% and 30.08%, respectively).

CONCLUSIONS

The prostate cancer detection rate for a PSA level between 2.5 and 4.0 ng/mL was similar (27.48%) to that for the PSA range of 4.0 to 10.0 ng/mL (30.08%). The absolute cutpoint used to determine the need to evaluate a patient for prostate cancer by biopsy is not clear; however, many studies have suggested that 2.5 ng/mL may be a more appropriate cutpoint than 4.0 ng/mL.