title: Risk-stratification based on magnetic resonance imaging and prostate-specific antigen density may reduce unnecessary follow-up biopsy procedures in men on active surveillance for low-risk prostate cancer.
abstract: To assess the value of risk-stratification based on magnetic resonance imaging (MRI) and prostate-specific antigen density (PSA-D) in reducing unnecessary biopsies without missing Gleason pattern 4 prostate cancer in men on active surveillance (AS).
  
  
  
  In all, 210 men on AS with Gleason score 3 + 3 prostate cancer received a first MRI and if indicated [Prostate Imaging Reporting and Data System (PI-RADS) score ≥3] targeted biopsy (TBx) using MRI-transrectal ultrasonography (TRUS) fusion. The MRI was performed 3 months after diagnosis (group A: n = 97), at confirmatory biopsy (group B: n = 39) or at surveillance biopsy after one or more repeat TRUS-guided systematic biopsies (TRUS-Bx) (group C: n = 74). The primary outcome was upgrading to Gleason score ≥3 + 4 prostate cancer based on MRI ± TBx in groups A, B and C. Biopsy outcomes were stratified for the overall PI-RADS score and PSA-D to identify a subgroup of men in whom a biopsy could have been avoided as no Gleason score upgrading was detected.
  
  
  
  In all, 134/210 (64%) men had a positive MRI and 51/210 (24%) men had Gleason score upgrading based on MRI-TBx. The percentage of Gleason score upgrading based on MRI-TBx was 23% (22/97), 23% (9/39) and 27% (20/74) in respectively groups A, B and C. Additional Gleason score upgrading detected by TRUS-Bx occurred in 8% (3/39) of men in group B and 6% (1/17) of men who received TRUS-Bx in group C. No Gleason score upgrading was detected by MRI-TBx in men with a PI-RADS score of 3 and a PSA-D of <0.15 ng/mL2(n = 15), nor by TRUS-Bx in men with a PI-RADS score of 1-3 and a PSA-D of <0.15 ng/mL2(n = 15).
  
  
  
  At least one out of five men on AS with Gleason score 3 + 3 prostate cancer at diagnostic TRUS-Bx show Gleason score upgrading based on first MRI ± TBx at baseline, confirmatory or surveillance biopsy. Men with a PI-RADS score of 1-3 and PSA-D of <0.15 ng/mL2did not show Gleason score upgrading at MRI ± TBx or TRUS-Bx at each time point of surveillance. Thus risk-stratification based on PI-RADS and PSA-D may reduce unnecessary follow-up biopsy procedures in men on AS.
authors.affiliation: Department of Urology, Erasmus University Medical Center, Rotterdam, The Netherlands.
authors.forename: Arnout R
authors.identifier: 0000-0003-4358-2840
authors.initials: AR
authors.lastname: Alberts
authors.affiliation: Department of Urology, Erasmus University Medical Center, Rotterdam, The Netherlands.
authors.forename: Monique J
authors.initials: MJ
authors.lastname: Roobol
authors.affiliation: Department of Urology, Erasmus University Medical Center, Rotterdam, The Netherlands.|Department of Radiology, Erasmus University Medical Center, Rotterdam, The Netherlands.
authors.forename: Frank-Jan H
authors.initials: FH
authors.lastname: Drost
authors.affiliation: Department of Pathology, Erasmus University Medical Center, Rotterdam, The Netherlands.
authors.forename: Geert J
authors.initials: GJ
authors.lastname: van Leenders
authors.affiliation: Department of Urology, Erasmus University Medical Center, Rotterdam, The Netherlands.
authors.forename: Leonard P
authors.initials: LP
authors.lastname: Bokhorst
authors.affiliation: Department of Urology, Erasmus University Medical Center, Rotterdam, The Netherlands.
authors.forename: Chris H
authors.initials: CH
authors.lastname: Bangma
authors.affiliation: Department of Radiology, Erasmus University Medical Center, Rotterdam, The Netherlands.
authors.forename: Ivo G
authors.initials: IG
authors.lastname: Schoots
mesh_terms: D000368:Aged; D001707:Biopsy, Needle; D015331:Cohort Studies; D005500:Follow-Up Studies; D006801:Humans; D061705:Image-Guided Biopsy / Q000379:methods; D007150:Immunohistochemistry; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D060787:Neoplasm Grading; D009426:Netherlands; D017430:Prostate-Specific Antigen / Q000097:blood*; D011471:Prostatic Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology* / Q000628:therapy; D012189:Retrospective Studies; D018570:Risk Assessment; D013997:Time Factors; D019564:Unnecessary Procedures; D057832:Watchful Waiting
chemical_list: D017430:Prostate-Specific Antigen
keywords: #PCSM; #ProstateCancer; PSA density; active surveillance; magnetic resonance imaging; target biopsy