The Prostate Health Index in predicting initial prostate biopsy outcomes in Asian men with prostate-specific antigen levels of 4–10 ng/mL

Abstract

To investigate the role of the Prostate Health Index (phi) in prostate cancer (PCa) detection in patients with a prostate-specific antigen (PSA) level of 4-10 ng/mL receiving their first prostatic biopsy in an Asian population. This was a retrospective study of archived serum samples from patients enlisted in our tissue bank. Patients over 50 years old, with PSA level of 4-10 ng/mL, a negative digital rectal examination, and received their first prostatic biopsy between April 2008 and April 2013, were recruited. The serum sample collected before biopsy was retrieved for the measurement of various PSA derivatives and the phi value was calculated for each patient. The performance of these parameters in predicting the prostatic biopsy results was assessed. Two hundred and thirty consecutive patients, with 21 (9.13 %) diagnosed with PCa, were recruited for this study. Statistically significant differences between PCa patients and non-PCa patients were found for total PSA, PSA density, [-2]proPSA (p2PSA), free-to-total PSA ratio (%fPSA), p2PSA-to-free PSA ratio (%p2PSA), and phi. The areas under the curve of the receiver operating characteristic curve for total PSA, PSA density, %fPSA, %p2PSA, and phi were 0.547, 0.634, 0.654, 0.768, and 0.781, respectively. The phi was the best predictor of the prostatic biopsies results. At a sensitivity of 90 %, the use of the phi could have avoided unnecessary biopsies in 104 (45.2 %) patients. Use of the phi could improve the accuracy of PCa detection in patients with an elevated PSA level and thus avoid unnecessary prostatic biopsies.