title: Interobserver Reproducibility of the PI-RADS Version 2 Lexicon: A Multicenter Study of Six Experienced Prostate Radiologists.
abstract: Purpose To determine the interobserver reproducibility of the Prostate Imaging Reporting and Data System (PI-RADS) version 2 lexicon. Materials and Methods This retrospective HIPAA-compliant study was institutional review board-approved. Six radiologists from six separate institutions, all experienced in prostate magnetic resonance (MR) imaging, assessed prostate MR imaging examinations performed at a single center by using the PI-RADS lexicon. Readers were provided screen captures that denoted the location of one specific lesion per case. Analysis entailed two sessions (40 and 80 examinations per session) and an intersession training period for individualized feedback and group discussion. Percent agreement (fraction of pairwise reader combinations with concordant readings) was compared between sessions. κ coefficients were computed. Results No substantial difference in interobserver agreement was observed between sessions, and the sessions were subsequently pooled. Agreement for PI-RADS score of 4 or greater was 0.593 in peripheral zone (PZ) and 0.509 in transition zone (TZ). In PZ, reproducibility was moderate to substantial for features related to diffusion-weighted imaging (κ = 0.535-0.619); fair to moderate for features related to dynamic contrast material-enhanced (DCE) imaging (κ = 0.266-0.439); and fair for definite extraprostatic extension on T2-weighted images (κ = 0.289). In TZ, reproducibility for features related to lesion texture and margins on T2-weighted images ranged from 0.136 (moderately hypointense) to 0.529 (encapsulation). Among 63 lesions that underwent targeted biopsy, classification as PI-RADS score of 4 or greater by a majority of readers yielded tumor with a Gleason score of 3+4 or greater in 45.9% (17 of 37), without missing any tumor with a Gleason score of 3+4 or greater. Conclusion Experienced radiologists achieved moderate reproducibility for PI-RADS version 2, and neither required nor benefitted from a training session. Agreement tended to be better in PZ than TZ, although was weak for DCE in PZ. The findings may help guide future PI-RADS lexicon updates. (©) RSNA, 2016 Online supplemental material is available for this article.
authors.affiliation: From the Department of Radiology, NYU School of Medicine, NYU Langone Medical Center, 660 1st Ave, Third Floor, New York, NY 10016 (A.B.R., L.A.G., J.S.B.); Department of Radiology, Yale School of Medicine, New Haven, Conn (D.C.); Department of Radiology, Mayo Clinic, Rochester, Minn (A.T.F.); Department of Radiology, Duke University Medical Center, Duke Cancer Institute, Durham, NC (R.T.G.); Molecular Imaging Program, National Cancer Institute, National Institutes of Health, Bethesda, Md (B.T.); Departments of Radiology and Biomedical Imaging and Urology, University of California-San Francisco, San Francisco, Calif (A.C.W.); and Department of Radiology, David Geffen School of Medicine at UCLA, Los Angeles, Calif (D.J.M.).
authors.forename: Andrew B
authors.initials: AB
authors.lastname: Rosenkrantz
authors.affiliation: From the Department of Radiology, NYU School of Medicine, NYU Langone Medical Center, 660 1st Ave, Third Floor, New York, NY 10016 (A.B.R., L.A.G., J.S.B.); Department of Radiology, Yale School of Medicine, New Haven, Conn (D.C.); Department of Radiology, Mayo Clinic, Rochester, Minn (A.T.F.); Department of Radiology, Duke University Medical Center, Duke Cancer Institute, Durham, NC (R.T.G.); Molecular Imaging Program, National Cancer Institute, National Institutes of Health, Bethesda, Md (B.T.); Departments of Radiology and Biomedical Imaging and Urology, University of California-San Francisco, San Francisco, Calif (A.C.W.); and Department of Radiology, David Geffen School of Medicine at UCLA, Los Angeles, Calif (D.J.M.).
authors.forename: Luke A
authors.initials: LA
authors.lastname: Ginocchio
authors.affiliation: From the Department of Radiology, NYU School of Medicine, NYU Langone Medical Center, 660 1st Ave, Third Floor, New York, NY 10016 (A.B.R., L.A.G., J.S.B.); Department of Radiology, Yale School of Medicine, New Haven, Conn (D.C.); Department of Radiology, Mayo Clinic, Rochester, Minn (A.T.F.); Department of Radiology, Duke University Medical Center, Duke Cancer Institute, Durham, NC (R.T.G.); Molecular Imaging Program, National Cancer Institute, National Institutes of Health, Bethesda, Md (B.T.); Departments of Radiology and Biomedical Imaging and Urology, University of California-San Francisco, San Francisco, Calif (A.C.W.); and Department of Radiology, David Geffen School of Medicine at UCLA, Los Angeles, Calif (D.J.M.).
authors.forename: Daniel
authors.initials: D
authors.lastname: Cornfeld
authors.affiliation: From the Department of Radiology, NYU School of Medicine, NYU Langone Medical Center, 660 1st Ave, Third Floor, New York, NY 10016 (A.B.R., L.A.G., J.S.B.); Department of Radiology, Yale School of Medicine, New Haven, Conn (D.C.); Department of Radiology, Mayo Clinic, Rochester, Minn (A.T.F.); Department of Radiology, Duke University Medical Center, Duke Cancer Institute, Durham, NC (R.T.G.); Molecular Imaging Program, National Cancer Institute, National Institutes of Health, Bethesda, Md (B.T.); Departments of Radiology and Biomedical Imaging and Urology, University of California-San Francisco, San Francisco, Calif (A.C.W.); and Department of Radiology, David Geffen School of Medicine at UCLA, Los Angeles, Calif (D.J.M.).
authors.forename: Adam T
authors.initials: AT
authors.lastname: Froemming
authors.affiliation: From the Department of Radiology, NYU School of Medicine, NYU Langone Medical Center, 660 1st Ave, Third Floor, New York, NY 10016 (A.B.R., L.A.G., J.S.B.); Department of Radiology, Yale School of Medicine, New Haven, Conn (D.C.); Department of Radiology, Mayo Clinic, Rochester, Minn (A.T.F.); Department of Radiology, Duke University Medical Center, Duke Cancer Institute, Durham, NC (R.T.G.); Molecular Imaging Program, National Cancer Institute, National Institutes of Health, Bethesda, Md (B.T.); Departments of Radiology and Biomedical Imaging and Urology, University of California-San Francisco, San Francisco, Calif (A.C.W.); and Department of Radiology, David Geffen School of Medicine at UCLA, Los Angeles, Calif (D.J.M.).
authors.forename: Rajan T
authors.initials: RT
authors.lastname: Gupta
authors.affiliation: From the Department of Radiology, NYU School of Medicine, NYU Langone Medical Center, 660 1st Ave, Third Floor, New York, NY 10016 (A.B.R., L.A.G., J.S.B.); Department of Radiology, Yale School of Medicine, New Haven, Conn (D.C.); Department of Radiology, Mayo Clinic, Rochester, Minn (A.T.F.); Department of Radiology, Duke University Medical Center, Duke Cancer Institute, Durham, NC (R.T.G.); Molecular Imaging Program, National Cancer Institute, National Institutes of Health, Bethesda, Md (B.T.); Departments of Radiology and Biomedical Imaging and Urology, University of California-San Francisco, San Francisco, Calif (A.C.W.); and Department of Radiology, David Geffen School of Medicine at UCLA, Los Angeles, Calif (D.J.M.).
authors.forename: Baris
authors.initials: B
authors.lastname: Turkbey
authors.affiliation: From the Department of Radiology, NYU School of Medicine, NYU Langone Medical Center, 660 1st Ave, Third Floor, New York, NY 10016 (A.B.R., L.A.G., J.S.B.); Department of Radiology, Yale School of Medicine, New Haven, Conn (D.C.); Department of Radiology, Mayo Clinic, Rochester, Minn (A.T.F.); Department of Radiology, Duke University Medical Center, Duke Cancer Institute, Durham, NC (R.T.G.); Molecular Imaging Program, National Cancer Institute, National Institutes of Health, Bethesda, Md (B.T.); Departments of Radiology and Biomedical Imaging and Urology, University of California-San Francisco, San Francisco, Calif (A.C.W.); and Department of Radiology, David Geffen School of Medicine at UCLA, Los Angeles, Calif (D.J.M.).
authors.forename: Antonio C
authors.initials: AC
authors.lastname: Westphalen
authors.affiliation: From the Department of Radiology, NYU School of Medicine, NYU Langone Medical Center, 660 1st Ave, Third Floor, New York, NY 10016 (A.B.R., L.A.G., J.S.B.); Department of Radiology, Yale School of Medicine, New Haven, Conn (D.C.); Department of Radiology, Mayo Clinic, Rochester, Minn (A.T.F.); Department of Radiology, Duke University Medical Center, Duke Cancer Institute, Durham, NC (R.T.G.); Molecular Imaging Program, National Cancer Institute, National Institutes of Health, Bethesda, Md (B.T.); Departments of Radiology and Biomedical Imaging and Urology, University of California-San Francisco, San Francisco, Calif (A.C.W.); and Department of Radiology, David Geffen School of Medicine at UCLA, Los Angeles, Calif (D.J.M.).
authors.forename: James S
authors.initials: JS
authors.lastname: Babb
authors.affiliation: From the Department of Radiology, NYU School of Medicine, NYU Langone Medical Center, 660 1st Ave, Third Floor, New York, NY 10016 (A.B.R., L.A.G., J.S.B.); Department of Radiology, Yale School of Medicine, New Haven, Conn (D.C.); Department of Radiology, Mayo Clinic, Rochester, Minn (A.T.F.); Department of Radiology, Duke University Medical Center, Duke Cancer Institute, Durham, NC (R.T.G.); Molecular Imaging Program, National Cancer Institute, National Institutes of Health, Bethesda, Md (B.T.); Departments of Radiology and Biomedical Imaging and Urology, University of California-San Francisco, San Francisco, Calif (A.C.W.); and Department of Radiology, David Geffen School of Medicine at UCLA, Los Angeles, Calif (D.J.M.).
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Margolis
mesh_terms: D000328:Adult; D000368:Aged; D001706:Biopsy; D003287:Contrast Media; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D060787:Neoplasm Grading; D009942:Organometallic Compounds; D010818:Practice Patterns, Physicians' / Q000706:statistics & numerical data*; D011469:Prostatic Diseases / Q000000981:diagnostic imaging* / Q000473:pathology; D015203:Reproducibility of Results; D012189:Retrospective Studies
chemical_list: D003287:Contrast Media; D009942:Organometallic Compounds; C090600:gadobutrol