title: Prostate Specific Membrane Antigen Positron Emission Tomography May Improve the Diagnostic Accuracy of Multiparametric Magnetic Resonance Imaging in Localized Prostate Cancer.
abstract: OBJECTIVE
  Positron emission tomography using ligands targeting prostate specific membrane antigen has recently been introduced. Positron emission tomography imaging with (68)Ga-PSMA-HBED-CC has been shown to detect metastatic prostate cancer lesions at a high rate. In this study we compare multiparametric magnetic resonance imaging and prostate specific membrane antigen positron emission tomography of the prostate with whole mount ex vivo prostate histopathology to determine the true sensitivity and specificity of these imaging modalities for detecting and locating tumor foci within the prostate.
  
  
  METHODS
  In a prospective clinical trial setting 20 patients with localized prostate cancer and a planned radical prostatectomy were recruited. All patients underwent multiparametric magnetic resonance imaging and positron emission tomography before surgery, and whole mount histopathology slides were directly compared to the images. European Society of Urogenital Radiology guidelines for reporting magnetic resonance imaging were used as a template for regional units of analysis. The uropathologist and radiologists were blinded to individual components of the study, and the final correlation was performed by visual and deformable registration analysis.
  
  
  RESULTS
  A total of 50 clinically significant lesions were identified from the whole mount histopathological analysis. Based on regional analysis the sensitivity, specificity, positive predictive value and negative predictive value for multiparametric magnetic resonance imaging were 44%, 94%, 81% and 76%, respectively. With prostate specific membrane antigen positron emission tomography the sensitivity, specificity, positive predictive value and negative predictive value were 49%, 95%, 85% and 88%, respectively. Prostate specific membrane antigen positron emission tomography yielded a higher specificity and positive predictive value.
  
  
  CONCLUSIONS
  A significant proportion of cancers are potentially missed and underestimated by both imaging modalities. Prostate specific membrane antigen positron emission tomography may be used in addition to multiparametric magnetic resonance imaging to help improve local staging in those patients undergoing retropubic radical prostatectomy.
authors.affiliation: Department of Urology, Princess Alexandra Hospital, Queensland, Australia; Australian Prostate Cancer Research Centre-Queensland, Institute of Health and Biomedical Innovation, Faculty of Health, Queensland University of Technology, Princess Alexandra Hospital, Translational Research Institute, Queensland, Australia. Electronic address: handoorhee@gmail.com.
authors.forename: H
authors.initials: H
authors.lastname: Rhee
authors.affiliation: Department of Nuclear Medicine, Royal Brisbane and Women's Hospital, Queensland, Australia.
authors.forename: P
authors.initials: P
authors.lastname: Thomas
authors.affiliation: Pathology Queensland, Princess Alexandra Hospital, Queensland, Australia.
authors.forename: B
authors.initials: B
authors.lastname: Shepherd
authors.affiliation: Department of Radiology, Princess Alexandra Hospital, Queensland, Australia.
authors.forename: S
authors.initials: S
authors.lastname: Gustafson
authors.affiliation: Department of Urology, Princess Alexandra Hospital, Queensland, Australia; Australian Prostate Cancer Research Centre-Queensland, Institute of Health and Biomedical Innovation, Faculty of Health, Queensland University of Technology, Princess Alexandra Hospital, Translational Research Institute, Queensland, Australia.
authors.forename: I
authors.initials: I
authors.lastname: Vela
authors.affiliation: Australian Prostate Cancer Research Centre-Queensland, Institute of Health and Biomedical Innovation, Faculty of Health, Queensland University of Technology, Princess Alexandra Hospital, Translational Research Institute, Queensland, Australia.
authors.forename: P J
authors.initials: PJ
authors.lastname: Russell
authors.affiliation: Australian Prostate Cancer Research Centre-Queensland, Institute of Health and Biomedical Innovation, Faculty of Health, Queensland University of Technology, Princess Alexandra Hospital, Translational Research Institute, Queensland, Australia.
authors.forename: C
authors.initials: C
authors.lastname: Nelson
authors.affiliation: Department of Urology, Princess Alexandra Hospital, Queensland, Australia.
authors.forename: E
authors.initials: E
authors.lastname: Chung
authors.affiliation: Department of Urology, Greenslopes Private Hospital, Queensland, Australia.
authors.forename: G
authors.initials: G
authors.lastname: Wood
authors.affiliation: Department of Urology, Princess Alexandra Hospital, Queensland, Australia; Department of Urology, Greenslopes Private Hospital, Queensland, Australia.
authors.forename: G
authors.initials: G
authors.lastname: Malone
authors.affiliation: Department of Urology, Princess Alexandra Hospital, Queensland, Australia; Department of Urology, Greenslopes Private Hospital, Queensland, Australia.
authors.forename: S
authors.initials: S
authors.lastname: Wood
authors.affiliation: Department of Urology, Princess Alexandra Hospital, Queensland, Australia; Department of Urology, Greenslopes Private Hospital, Queensland, Australia; Australian Prostate Cancer Research Centre-Queensland, Institute of Health and Biomedical Innovation, Faculty of Health, Queensland University of Technology, Princess Alexandra Hospital, Translational Research Institute, Queensland, Australia.
authors.forename: P
authors.initials: P
authors.lastname: Heathcote
mesh_terms: D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D049268:Positron-Emission Tomography / Q000379:methods*; D011446:Prospective Studies; D011467:Prostate / Q000000981:diagnostic imaging*; D011471:Prostatic Neoplasms / Q000175:diagnosis* / Q000378:metabolism; D015203:Reproducibility of Results
keywords: magnetic resonance imaging; pathology; positron-emission tomography; prostate