title: Gleason score at diagnosis predicts the rate of detection of 18F-choline PET/CT performed when biochemical evidence indicates recurrence of prostate cancer: experience with 1,000 patients.
abstract: The objective of this study was to explore the ability of the initial Gleason score (GS) to predict the rate of detection of recurrent prostate cancer (PCa) with (18)F-choline PET/CT in a large cohort of patients.
  
  
  METHODS
  Data from 1,000 patients who had undergone (18)F-choline PET/CT because of biochemical evidence of relapse of PCa between 2004 and 2013 were retrieved from databases at 4 centers. Continuous data were compared by the Student t test or ANOVA, and categoric variables were compared by the χ(2) test. Univariable and multivariable analyses were performed by logistic regression.
  
  
  RESULTS
  The GS at diagnosis was less than or equal to 6 in 257 patients, 7 in 347 patients, and greater than 7 in 396 patients. The results of 645 PET/CT scans were positive for PCa recurrence. Eighty-one percent of the positive PET/CT results were found in patients with a PSA level of greater than or equal to 2 ng/mL, 43% were found in patients with a PSA level of 1-2 ng/mL, and 31% were found in patients with a PSA level of less than or equal to 1 ng/mL; 78.8% of patients with positive PET/CT results had a GS of greater than 7. The results of (18)F-choline PET/CT scans were negative in 300 patients; 44% had a GS of less than or equal to 6, 35% had a GS of 7, and 17% had a GS of greater than 7. PET/CT results were rated as doubtful in only 5.5% of patients (median PSA, 1.8 ng/mL). When the GS was greater than 7, the rates of detection of (18)F-choline PET/CT were 51%, 65%, and 91% for a PSA level of less than 1 ng/mL, 1-2 ng/mL, and greater than 2 ng/mL, respectively. In univariable and multivariable analyses, both a GS of 7 and a GS of greater than 7 were independent predictors for positive (18)F-choline PET/CT results (odds ratios, 0.226 and 0.330, respectively; P values for both, <0.001).
  
  
  CONCLUSIONS
  A high GS at diagnosis is a strong predictive factor for positive (18)F-choline PET/CT scan results for recurrent PCa, even when the PSA level is low (i.e., ≤1 ng/mL).
authors.affiliation: Nuclear Medicine Unit, IRCCS National Cancer Institute (CRO), Aviano, Italy.
authors.forename: Marino
authors.initials: M
authors.lastname: Cimitan
authors.affiliation: Radiotherapy and Nuclear Medicine Unit, Veneto Institute of Oncology, IRCCS, Padua, Italy laura.evangelista@ioveneto.it.
authors.forename: Laura
authors.initials: L
authors.lastname: Evangelista
authors.affiliation: Nuclear Medicine Department, University Medical Center Ljubljana, Ljubljana, Slovenia; and.
authors.forename: Marina
authors.initials: M
authors.lastname: Hodolič
authors.affiliation: Regional Center of Nuclear Medicine, University of Pisa, Pisa, Italy.
authors.forename: Giuliano
authors.initials: G
authors.lastname: Mariani
authors.affiliation: Nuclear Medicine Unit, IRCCS National Cancer Institute (CRO), Aviano, Italy.
authors.forename: Tanja
authors.initials: T
authors.lastname: Baseric
authors.affiliation: Nuclear Medicine Unit, IRCCS National Cancer Institute (CRO), Aviano, Italy.
authors.forename: Valentina
authors.initials: V
authors.lastname: Bodanza
authors.affiliation: Radiotherapy and Nuclear Medicine Unit, Veneto Institute of Oncology, IRCCS, Padua, Italy.
authors.forename: Giorgio
authors.initials: G
authors.lastname: Saladini
authors.affiliation: Regional Center of Nuclear Medicine, University of Pisa, Pisa, Italy.
authors.forename: Duccio
authors.initials: D
authors.lastname: Volterrani
authors.affiliation: Radiotherapy and Nuclear Medicine Unit, Veneto Institute of Oncology, IRCCS, Padua, Italy.
authors.forename: Anna Rita
authors.initials: AR
authors.lastname: Cervino
authors.affiliation: Radiotherapy and Nuclear Medicine Unit, Veneto Institute of Oncology, IRCCS, Padua, Italy.
authors.forename: Michele
authors.initials: M
authors.lastname: Gregianin
authors.affiliation: Regional Center of Nuclear Medicine, University of Pisa, Pisa, Italy.
authors.forename: Giulia
authors.initials: G
authors.lastname: Puccini
authors.affiliation: Regional Center of Nuclear Medicine, University of Pisa, Pisa, Italy.
authors.forename: Federica
authors.initials: F
authors.lastname: Guidoccio
authors.affiliation: Nuclear Medicine Department, University Medical Center Ljubljana, Ljubljana, Slovenia; and.
authors.forename: Jure
authors.initials: J
authors.lastname: Fettich
authors.affiliation: Nuclear Medicine Unit, IRCCS National Cancer Institute (CRO), Aviano, Italy.
authors.forename: Eugenio
authors.initials: E
authors.lastname: Borsatti
mesh_terms: D000368:Aged; D000704:Analysis of Variance; D001706:Biopsy; D002794:Choline / Q000031:analogs & derivatives*; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D060787:Neoplasm Grading; D009364:Neoplasm Recurrence, Local / Q000000981:diagnostic imaging*; D049268:Positron-Emission Tomography; D011237:Predictive Value of Tests; D017430:Prostate-Specific Antigen / Q000378:metabolism; D011471:Prostatic Neoplasms / Q000000981:diagnostic imaging*; D012372:ROC Curve; D012044:Regression Analysis; D012189:Retrospective Studies; D012306:Risk; D014057:Tomography, X-Ray Computed
chemical_list: C516370:fluoromethylcholine; D017430:Prostate-Specific Antigen; D002794:Choline
keywords: 18F-choline PET; Gleason score; PSA; prostate cancer; restaging