title: Role of 18F-choline PET/CT in biochemically relapsed prostate cancer after radical prostatectomy: correlation with trigger PSA, PSA velocity, PSA doubling time, and metastatic distribution.
abstract: OBJECTIVE
  The aim of this study was to evaluate the efficacy of ¹⁸F-choline PET/CT (18FCH-PET/CT) in restaging patients previously treated by radical prostatectomy for a prostate cancer, presenting with biochemical relapse during follow-up (FU).
  
  
  METHODS
  Three hundred thirty-one patients referred to us from January 2009 to April 2011 to perform 18FCH PET/CT were evaluated: 233 of them (mean age 69.7 years) met the inclusion criteria of the study: (1) biochemical relapse after radical prostatectomy (trigger PSA>0.2 ng/mL) (n=224) and (2) high risk for relapse (elevated Gleason score≥8) in spite PSA<0.1 ng/mL during FU (n=9). Trigger PSA was available for all patients (mean 8 ng/mL) and in 44 of them also PSA kinetic (PSA velocity-PSAvel; PSA doubling time-PSAdt). Correlation between 18FCH PET/CT detection rate and trigger PSA, PSAvel, PSAdt, and tumoral spread distribution were evaluated by univariate and multivariate analysis. Subsequent minimum FU was 1 year (mean 26 months, range 12-40).
  
  
  RESULTS
  Overall detection rate of 18FCH PET/CT was 54%, which significantly increased when the trigger PSA increases (P<0.001). PET-positive patients presented a "fast" PSA kinetic (mean PSAdt=6 months and mean PSAvel=9.3 ng/mL/yr), while PET-negative patients presented a "slow" PSA kinetic (mean PSAdt=15.4 months and mean PSAvel=0.9 ng/mL/yr). Disease relapse was local in 17% of cases, distant in 66%, and combined in 17%.
  
  
  CONCLUSIONS
  Overall 18FCH PET/CT detection rate was 54% (ie, similar to that reported in literature with ¹¹C-choline), which increases with the increase in trigger PSA: this condition was particularly true in patients with accelerated PSA kinetic. In about 20% of patients, 18FCH PET/CT demonstrated local relapses early enough to offer locoregional radiation therapy.
authors.affiliation: Department of Nuclear Medicine, PET/CT Center, Medical Physics Unit, Santa Maria della Misericordia Hospital, Rovigo, Italy.
authors.forename: Maria Cristina
authors.initials: MC
authors.lastname: Marzola
authors.forename: Sotirios
authors.initials: S
authors.lastname: Chondrogiannis
authors.forename: Alice
authors.initials: A
authors.lastname: Ferretti
authors.forename: Gaia
authors.initials: G
authors.lastname: Grassetto
authors.forename: Lucia
authors.initials: L
authors.lastname: Rampin
authors.forename: Arianna
authors.initials: A
authors.lastname: Massaro
authors.forename: Paolo
authors.initials: P
authors.lastname: Castellucci
authors.forename: Maria
authors.initials: M
authors.lastname: Picchio
authors.forename: Adil
authors.initials: A
authors.lastname: Al-Nahhas
authors.forename: Patrick M
authors.initials: PM
authors.lastname: Colletti
authors.forename: Adriano
authors.initials: A
authors.lastname: Marcolongo
authors.forename: Domenico
authors.initials: D
authors.lastname: Rubello
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002794:Choline / Q000031:analogs & derivatives*; D006801:Humans; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging; D015999:Multivariate Analysis; D009362:Neoplasm Metastasis; D049268:Positron-Emission Tomography; D017430:Prostate-Specific Antigen / Q000378:metabolism*; D011468:Prostatectomy; D011471:Prostatic Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology* / Q000601:surgery; D012008:Recurrence; D014057:Tomography, X-Ray Computed
chemical_list: C516370:fluoromethylcholine; D017430:Prostate-Specific Antigen; D002794:Choline