title: Diagnostic accuracy of multi-parametric MRI and TRUS biopsy in prostate cancer (PROMIS): a paired validating confirmatory study.
abstract: Men with high serum prostate specific antigen usually undergo transrectal ultrasound-guided prostate biopsy (TRUS-biopsy). TRUS-biopsy can cause side-effects including bleeding, pain, and infection. Multi-parametric magnetic resonance imaging (MP-MRI) used as a triage test might allow men to avoid unnecessary TRUS-biopsy and improve diagnostic accuracy.
  
  
  
  We did this multicentre, paired-cohort, confirmatory study to test diagnostic accuracy of MP-MRI and TRUS-biopsy against a reference test (template prostate mapping biopsy [TPM-biopsy]). Men with prostate-specific antigen concentrations up to 15 ng/mL, with no previous biopsy, underwent 1·5 Tesla MP-MRI followed by both TRUS-biopsy and TPM-biopsy. The conduct and reporting of each test was done blind to other test results. Clinically significant cancer was defined as Gleason score ≥4 + 3 or a maximum cancer core length 6 mm or longer. This study is registered on ClinicalTrials.gov, NCT01292291.
  
  
  
  Between May 17, 2012, and November 9, 2015, we enrolled 740 men, 576 of whom underwent 1·5 Tesla MP-MRI followed by both TRUS-biopsy and TPM-biopsy. On TPM-biopsy, 408 (71%) of 576 men had cancer with 230 (40%) of 576 patients clinically significant. For clinically significant cancer, MP-MRI was more sensitive (93%, 95% CI 88-96%) than TRUS-biopsy (48%, 42-55%; p<0·0001) and less specific (41%, 36-46% for MP-MRI vs 96%, 94-98% for TRUS-biopsy; p<0·0001). 44 (5·9%) of 740 patients reported serious adverse events, including 8 cases of sepsis.
  
  
  
  Using MP-MRI to triage men might allow 27% of patients avoid a primary biopsy and diagnosis of 5% fewer clinically insignificant cancers. If subsequent TRUS-biopsies were directed by MP-MRI findings, up to 18% more cases of clinically significant cancer might be detected compared with the standard pathway of TRUS-biopsy for all. MP-MRI, used as a triage test before first prostate biopsy, could reduce unnecessary biopsies by a quarter. MP-MRI can also reduce over-diagnosis of clinically insignificant prostate cancer and improve detection of clinically significant cancer.
  
  
  
  PROMIS is funded by the UK Government Department of Health, National Institute of Health Research-Health Technology Assessment Programme, (Project number 09/22/67). This project is also supported and partly funded by UCLH/UCL Biomedical Research Centre and The Royal Marsden and Institute for Cancer Research Biomedical Research Centre and is coordinated by the Medical Research Council Clinical Trials Unit (MRC CTU) at UCL. It is sponsored by University College London (UCL).
authors.affiliation: Division of Surgery and Interventional Science, Faculty of Medical Sciences, University College London, London, UK; Department of Urology, UCLH NHS Foundation Trust, London, UK. Electronic address: hashim.ahmed@ucl.ac.uk.
authors.forename: Hashim U
authors.initials: HU
authors.lastname: Ahmed
authors.affiliation: Division of Surgery and Interventional Science, Faculty of Medical Sciences, University College London, London, UK; Department of Urology, UCLH NHS Foundation Trust, London, UK.
authors.forename: Ahmed
authors.initials: A
authors.lastname: El-Shater Bosaily
authors.affiliation: MRC Clinical Trials Unit at UCL, London, UK.
authors.forename: Louise C
authors.initials: LC
authors.lastname: Brown
authors.affiliation: Hull York Medical School and Department of Health Sciences, University of York, UK.
authors.forename: Rhian
authors.initials: R
authors.lastname: Gabe
authors.affiliation: MRC Clinical Trials Unit at UCL, London, UK.
authors.forename: Richard
authors.initials: R
authors.lastname: Kaplan
authors.affiliation: MRC Clinical Trials Unit at UCL, London, UK.
authors.forename: Mahesh K
authors.initials: MK
authors.lastname: Parmar
authors.affiliation: MRC Clinical Trials Unit at UCL, London, UK.
authors.forename: Yolanda
authors.initials: Y
authors.lastname: Collaco-Moraes
authors.affiliation: MRC Clinical Trials Unit at UCL, London, UK.
authors.forename: Katie
authors.initials: K
authors.lastname: Ward
authors.affiliation: Department of Urology, Hampshire Hospitals NHS Foundation Trust, UK.
authors.forename: Richard G
authors.initials: RG
authors.lastname: Hindley
authors.affiliation: Department of Histopathology, UCLH NHS Foundation Trust, London, UK.
authors.forename: Alex
authors.initials: A
authors.lastname: Freeman
authors.affiliation: Department of Radiology, UCLH NHS Foundation Trust, London, UK.
authors.forename: Alex P
authors.initials: AP
authors.lastname: Kirkham
authors.affiliation: Public and patient representative, Nottingham, UK.
authors.forename: Robert
authors.initials: R
authors.lastname: Oldroyd
authors.affiliation: Department of Academic Urology, Royal Marsden Hospital, Sutton, UK.
authors.forename: Chris
authors.initials: C
authors.lastname: Parker
authors.affiliation: Division of Surgery and Interventional Science, Faculty of Medical Sciences, University College London, London, UK; Department of Urology, UCLH NHS Foundation Trust, London, UK.
authors.forename: Mark
authors.initials: M
authors.lastname: Emberton
mesh_terms: D006801:Humans; D061705:Image-Guided Biopsy / Q000379:methods*; D008279:Magnetic Resonance Imaging; D008297:Male; D060787:Neoplasm Grading; D011446:Prospective Studies; D017430:Prostate-Specific Antigen / Q000097:blood; D011471:Prostatic Neoplasms / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology; D012680:Sensitivity and Specificity; D018084:Ultrasonography, Interventional
chemical_list: D017430:Prostate-Specific Antigen