The effect of lowering the prostate-specific antigen normal cutoff on referral rates to urology.

Abstract

BACKGROUND: Routine prostate cancer screening is controversial, yet the use of prostate-specific antigen (PSA) for screening is likely to continue. Our hospital laboratory decreased the cutoff for normal PSA to 2.5 ng/mL on July 2, 2007, based on the National Comprehensive Screening Network recommendations. The purpose of this study was to determine if referral rates to urology increased after this change. METHODS: We queried our electronic health records to obtain the number of total screening PSA and abnormal PSA and subsequent referrals to urology in the 20-month periods before and after the change in PSA cutoff. RESULTS: There was no significant difference between the percentage of total screening PSA that resulted in a referral to urology after the change than before (7 of 199 [3.5%] vs 8 of 113 [7.1%]; P = .16). The percentage of abnormal PSA (as defined in the respective time periods) that were referred to urology actually decreased after the change (7 of 29 [24.1%] vs 6 of 10 [60.0%]; P = .04); however, when considering only PSA >4.0 ng/mL in each time period, there was no difference in percentage of referrals between the 2 periods. CONCLUSIONS: Contrary to expectations, lowering the cutoff for normal PSA did not increase referrals to urology.