Risk of upgrading from prostate biopsy to radical prostatectomy pathology: Is magnetic resonance imaging-guided biopsy more accurate?

Abstract

Background: This study compared magnetic resonance imaging-guided biopsy (MRI-GB) and transrectal ultrasound guided biopsy (TRUS-GB) with the final histology of the radical prostatectomy (RP) specimen. Methods: Our subjects were 229 patients with prostate cancer (PCa), proven histopathologically using MRI-GB or TRUS-GB, who underwent RP at our center between December 2015 and December 2016. The main group included 92 patients who underwent MRI-GB and the control group included 137 patients who underwent 12-core TRUS-GB. Histological findings for RP specimens were compared with those from biopsies. We also evaluated predictors of upgraded Gleason score (GS), using uni- and multivariate analyses. Results: Upgraded GS between biopsy and RP specimen occurred to 22.7% (52/229) of the cohort overall. In univariate analysis, prostate-specific antigen density (PSAD) (P<0.001), prostate volume (PV) < 30 ml (P<0.001), biopsy modality (P=0.027), biopsy GS (P=0.032) and measured MRI lymph node metastasis (P=0.018) were prognostic factors. Multivariate logistic regression analysis showed PV < 30 ml (P<0.001) and biopsy modality (P=0.001) were independent predictors of upgraded GS. Conclusions: MRI-GB may enhance the diagnostic accuracy of prostate cancer detection in final histopathology with lower rate of upgraded GS than TRUS-GB. Also, PV < 30 ml and biopsy modality were independent predictors of upgraded GS.

Keywords: Gleason score upgrading.; MRI; prostate biopsy; prostatectomy specimen; systematic biopsy.