The Utility of Prostate Specific Antigen Density, Prostate Health Index, and Prostate Health Index Density in Predicting Positive Prostate Biopsy Outcome is Dependent on the Prostate Biopsy Methods.

OBJECTIVE

To evaluate prognostic markers, prostate-specific antigen, prostate health index (PHI), and prostate volume indexed measures (prostate-specific antigen density and prostate health index density) for predicting positive prostate cancer biopsies in magnetic resonance (MR) transrectal ultrasound fused versus nonfused transrectal ultrasonography biopsy.

METHODS

A retrospective cohort of 211 patients that had at least 1 suspected MR lesion, Prostate Imaging-Reporting and Data System ≥3, and subsequent biopsy (2015-2017). Clinical characteristics and prognostic biomarkers were evaluated as predictors of prostate cancer detection by type of biopsy guidance (fused vs nonfused).

RESULTS

One-hundred twenty-one patients had nonfused and 90 had fused biopsies. PHI and PHID had greater area under the receiver operating characteristics curve (AUC) in predicting positive biopsies than prostate-specific antigen or PSAD for both nonfused and fused biopsy. PHI 0.78 (95% CI 0.67-0.88) and PHID 0.82 (95% CI 0.73-0.91) had the greatest AUC for predicting biopsy results for nonfused and fused biopsies, respectively. Multiple-variable models did not improve model fit compared to single variables. Based on Youden's index, a cut-off value of 45.9 for PHI in nonfused and 0.64 for PHID in fused biopsies would reduce the number of negative biopsies by 77.3% and 63.4%, respectively, but the percentage of missed clinically significant cancer biopsies would be 19% and 12%, respectively.

CONCLUSION

Our findings demonstrate that the choice of prognostic biomarkers for predicting positive biopsies is a function of the biopsy guidance method. Volume indexed derivatives appear to have greater value when a MRI-US fused method is used.