title: Predicting bone scan positivity in non-metastatic castration-resistant prostate cancer.
abstract: BACKGROUND
  To evaluate PSA levels and kinetic cutoffs to predict positive bone scans for men with non-metastatic castration-resistant prostate cancer (CRPC) from the Shared Equal Access Regional Cancer Hospital (SEARCH) cohort.
  
  
  METHODS
  Retrospective analysis of 531 bone scans of 312 clinically CRPC patients with no known metastases at baseline treated with a variety of primary treatment types in the SEARCH database. The association of patients' demographics, pathological features, PSA levels and kinetics with risk of a positive scan was tested using generalized estimating equations.
  
  
  RESULTS
  A total of 149 (28%) scans were positive. Positive scans were associated with younger age (odds ratio (OR)=0.98; P=0.014), higher Gleason scores (relative to Gleason 2-6, Gleason 3+4: OR=2.03, P=0.035; Gleason 4+3 and 8-10: OR=1.76, P=0.059), higher prescan PSA (OR=2.11; P<0.001), shorter prescan PSA doubling time (PSADT; OR=0.53; P<0.001), higher PSA velocity (OR=1.74; P<0.001) and more remote scan year (OR=0.92; P=0.004). Scan positivity was 6, 14, 29 and 57% for men with PSA<5, 5-14.9, 15-49.9 and ⩾ 50 ng ml(-1), respectively (P-trend <0.001). Men with PSADT ⩾ 15, 9-14.9, 3-8.9 and <3 months had a scan positivity of 11, 22, 34 and 47%, correspondingly (P-trend <0.001). Tables were constructed using PSA and PSADT to predict the likelihood of a positive bone scan.
  
  
  CONCLUSIONS
  PSA levels and kinetics were associated with positive bone scans. We developed tables to predict the risk of positive bone scans by PSA and PSADT. Combining PSA levels and kinetics may help select patients with CRPC for bone scans.
authors.affiliation: Department of Urology, Mayo Clinic, Rochester, MN, USA.
authors.forename: D M
authors.initials: DM
authors.lastname: Moreira
authors.affiliation: Department of Biostatistics and Bioinformatics, Duke University School of Medicine, Durham, NC, USA.|Urology Section, Veterans Affairs Medical Center Durham, Durham, NC, USA.|Division of Urology, Department of Surgery, and the Duke Prostate Center, Duke University School of Medicine, Durham, NC, USA.
authors.forename: L E
authors.initials: LE
authors.lastname: Howard
authors.affiliation: Urology Section, Veterans Affairs Medical Center Durham, Durham, NC, USA.|Division of Urology, Department of Surgery, and the Duke Prostate Center, Duke University School of Medicine, Durham, NC, USA.
authors.forename: K N
authors.initials: KN
authors.lastname: Sourbeer
authors.affiliation: Urology Section, Veterans Affairs Medical Center Durham, Durham, NC, USA.|Division of Urology, Department of Surgery, and the Duke Prostate Center, Duke University School of Medicine, Durham, NC, USA.
authors.forename: H S
authors.initials: HS
authors.lastname: Amarasekara
authors.affiliation: Urology Section, Veterans Affairs Medical Center Durham, Durham, NC, USA.|Division of Urology, Department of Surgery, and the Duke Prostate Center, Duke University School of Medicine, Durham, NC, USA.
authors.forename: L C
authors.initials: LC
authors.lastname: Chow
authors.affiliation: Urology Section, Veterans Affairs Medical Center Durham, Durham, NC, USA.|Division of Urology, Department of Surgery, and the Duke Prostate Center, Duke University School of Medicine, Durham, NC, USA.
authors.forename: D C
authors.initials: DC
authors.lastname: Cockrell
authors.affiliation: Urology Section, Veterans Affairs Medical Center Durham, Durham, NC, USA.|Division of Urology, Department of Surgery, and the Duke Prostate Center, Duke University School of Medicine, Durham, NC, USA.
authors.forename: B T
authors.initials: BT
authors.lastname: Hanyok
authors.affiliation: Urology Section, Veterans Affairs Medical Center Durham, Durham, NC, USA.|Division of Urology, Department of Surgery, and the Duke Prostate Center, Duke University School of Medicine, Durham, NC, USA.
authors.forename: C L
authors.initials: CL
authors.lastname: Pratson
authors.affiliation: Urology Section, Department of Surgery, Veterans Affairs Medical Center, Greater Los Angeles, Los Angeles, CA, USA.|Department of Urology, University of California at Los Angeles Medical Center, Los Angeles, CA, USA.
authors.forename: W J
authors.initials: WJ
authors.lastname: Aronson
authors.affiliation: Division of Urology, Department of Surgery, University of California at San Diego Medical Center, San Diego, CA, USA.
authors.forename: C J
authors.initials: CJ
authors.lastname: Kane
authors.affiliation: Urology Section, Division of Surgery, Veterans Affairs Medical Centers and Division of Urologic Surgery, Department of Surgery, Medical College of Georgia, Augusta, GA, USA.|Division of Urologic Surgery, Department of Surgery, Medical College of Georgia, Augusta, GA, USA.
authors.forename: M K
authors.initials: MK
authors.lastname: Terris
authors.affiliation: Division of Urology, Department of Surgery, Oregon Health & Science University, Portland, OR, USA.
authors.forename: C L
authors.initials: CL
authors.lastname: Amling
authors.affiliation: Department of Urology, University of California, San Francisco, San Francisco, CA, USA.|Department of Epidemiology & Biostatistics, University of California, San Francisco, San Francisco, CA, USA.|Urology Section, Department of Surgery, Veterans Affairs Medical Center, San Francisco, CA, USA.
authors.forename: M R
authors.initials: MR
authors.lastname: Cooperberg
authors.affiliation: Center for Observational Research, Amgen Inc., Thousand Oaks, CA, USA.
authors.forename: A
authors.initials: A
authors.lastname: Liede
authors.affiliation: Urology Section, Veterans Affairs Medical Center Durham, Durham, NC, USA.|Division of Urology, Department of Surgery, and the Duke Prostate Center, Duke University School of Medicine, Durham, NC, USA.|Department of Pathology, Duke University School of Medicine, Durham, NC, USA.
authors.forename: S J
authors.initials: SJ
authors.lastname: Freedland
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor; D001859:Bone Neoplasms / Q000175:diagnosis* / Q000556:secondary; D001842:Bone and Bones / Q000473:pathology; D006801:Humans; D008297:Male; D060787:Neoplasm Grading; D016017:Odds Ratio; D011379:Prognosis; D017430:Prostate-Specific Antigen / Q000097:blood*; D064129:Prostatic Neoplasms, Castration-Resistant / Q000097:blood* / Q000473:pathology / Q000628:therapy; D012680:Sensitivity and Specificity
chemical_list: D014408:Biomarkers, Tumor; D017430:Prostate-Specific Antigen