Prostate imaging-reporting and data system version 2 has improved biopsy tumor grade accuracy: a single, tertiary institutional experience

Abstract

Purpose: To investigate change in prostate biopsy accuracy regarding tumor grade before and after the release of Prostate Imaging-Reporting and Data System version 2 (PI-RADSv2) in a single tertiary institution.

Methods: We retrospectively evaluated 1191 patients with biopsy-proven prostate cancer (PCa) who had undergone prostate magnetic resonance imaging (MRI) and surgery before (2013 cohort, n = 394) and 5 years after PI-RADSv2 release (2020 cohort, n = 797). The highest tumor grade of each biopsy and surgical specimen was recorded, respectively. We compared concordant, underestimated, and overestimated biopsy rates regarding tumor grade to surgery between two cohorts, respectively. For patients who underwent both prostate MRI and biopsy at our institution, we investigated proportion of pre-biopsy MRI, age, and prostate-specific antigen of patients, and performed logistic regression to analyze which parameters are associated with concordant biopsy.

Results: Concordant and underestimated biopsy rates were significantly different between two cohorts: Concordance and underestimation rates were 47.2% and 46.3% in 2013 and 54.5% and 36.4% in 2020 (p = .019; p = .003), respectively. Overestimated biopsy rates were similar (p = .993). Proportion of pre-biopsy MRI was significantly higher in 2020 than in 2013 (80.9% versus 4.9%; p < .001), and was independently associated with concordant biopsy results in multivariate analysis (odds ratio = 1.486; 95% confidence interval, 1.057-2.089; p = .022).

Conclusions: There was a significant change in proportion of pre-biopsy MRI before and after the release of PI-RADSv2 in patients who underwent surgery for PCa. This change appears to have improved biopsy accuracy regarding tumor grade by reducing underestimation.

Keywords: Biopsy; Grade; Magnetic resonance imaging; Prostate.