title: C11-acetate and F-18 FDG PET for men with prostate cancer bone metastases: relative findings and response to therapy.
abstract: OBJECTIVE
  This study tested the feasibility of C11-acetate (acetate) positron emission tomography (PET) imaging to assess response to therapy in men with bone metastatic prostate cancer and compared results for disease detection and response evaluation with F-18 fluorodeoxyglucose (FDG) PET.
  
  
  METHODS
  Men with ≥3 prostate cancer bone metastases identified by Tc-99m methylene diphosphonate (MDP) bone scintigraphy and/or computed tomography were enrolled in a prospective study of serial acetate and FDG PET imaging. Patients were imaged before and 6 to 12 weeks after initial androgen deprivation therapy for new metastatic prostate cancer or first-line chemotherapy with docetaxel for castration-resistant prostate cancer. Qualitative assessment and changes in the tumor:normal uptake ratio were used to assess response by both acetate and FDG PET. In addition, the detection of bone metastases pretherapy was compared for acetate and FDG PET.
  
  
  RESULTS
  A total of 8 patients with documented bone metastases were imaged, of which 6 were imaged both pre- and post-therapy. Acetate PET detected bone metastases in all 8 patients, whereas FDG PET detected lesions in 6 of the 7 imaged patients. Acetate PET generally detected more metastases with a higher tumor:normal uptake ratio. Qualitative and quantitative assessments of post-treatment response correlated with composite clinical designations of response, stable disease, or progression in 6 of 6 and 5 of 6 by acetate and 4 of 5 and 3 of 5 by FDG PET, respectively.
  
  
  CONCLUSIONS
  In this pilot study, results indicate that acetate PET holds promise for response assessment of prostate cancer bone metastases and is complementary to FDG PET in bone metastasis detection.
authors.affiliation: Division of Oncology, Department of Medicine, University of Washington and Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA. evanyu@uw.edu
authors.forename: Evan Y
authors.initials: EY
authors.lastname: Yu
authors.forename: Mark
authors.initials: M
authors.lastname: Muzi
authors.forename: Joy A
authors.initials: JA
authors.lastname: Hackenbracht
authors.forename: Brian B
authors.initials: BB
authors.lastname: Rezvani
authors.forename: Jeanne M
authors.initials: JM
authors.lastname: Link
authors.forename: Robert Bruce
authors.initials: RB
authors.lastname: Montgomery
authors.forename: Celestia S
authors.initials: CS
authors.lastname: Higano
authors.forename: Janet F
authors.initials: JF
authors.lastname: Eary
authors.forename: David A
authors.initials: DA
authors.lastname: Mankoff
mesh_terms: D000085:Acetates; D001859:Bone Neoplasms / Q000000981:diagnostic imaging* / Q000556:secondary*; D002244:Carbon; D000077143:Docetaxel; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008297:Male; D049268:Positron-Emission Tomography; D011471:Prostatic Neoplasms / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000473:pathology*; D043823:Taxoids / Q000627:therapeutic use; D016896:Treatment Outcome
chemical_list: D000085:Acetates; D043823:Taxoids; C438206:carbon-11 acetate; D019788:Fluorodeoxyglucose F18; D000077143:Docetaxel; D002244:Carbon