title: Preliminary clinical experience of trans-1-Amino-3-(18)F-fluorocyclobutanecarboxylic Acid (anti-(18)F-FACBC) PET/CT imaging in prostate cancer patients.
abstract: BACKGROUND
  In this retrospective analysis we assessed the role of [(18)F]-FACBC-PET/CT in the prostatic cancer staging.
  
  
  METHODS
  30 first [(18)F]-FACBC-PET/CT images of 26 patients (68.1 ± 5.8 years) were analyzed. PET/CT findings were compared with PSA concentrations, with PSA doubling times (PDT), and with correlative imaging.
  
  
  RESULTS
  On 16 [(18)F]-FACBC (53.3%) scans, 58 metabolically active lesions were found. 12 (20.7%) lesions corresponding to the local relapse were found in prostate/prostate bed and seminal vesicles, 9 (15.5%) lesions were located in regional lymph nodes, 10 (17.2%) were located in distal lymph nodes, and 26 (44.8%) metabolically active lesions were found in the skeleton. In one case, focal uptake was found in the brain, confirmed further on MRI as meningioma. The mean S-PSA level in patients with positive [(18)F]-FACBC findings was 9.5 ± 16.9  μ g/L (0.54-69  μ g/L) and in patients with negative [(18)F]-FACBC findings was 1.96 ± 1.87  μ g/L (0.11-5.9  μ g/L), but the difference was not statistically significant. However, the PSA doubling time (PDT) in patients with positive findings was significantly shorter than PDT in patients with negative findings: 3.25 ± 2.09 months (0.3-6 months) versus 31.2 ± 22.02 months (8-84 months), P < 0.0001. There was a strong positive correlation between PSA value and number of metabolically active lesions (R = 0.74) and a negative correlation between PDT and number of metabolically active lesions (R = -0.56). There was a weak negative correlation between PDT and SUVmax⁡ (R = -0.30).
  
  
  CONCLUSIONS
  According to our preliminary clinical experience, [(18)F]-FACBC-PET may play a role in in vivo restaging of an active prostate cancer, especially in patients with a short S-PSA doubling time.
authors.affiliation: Department of Molecular Radiotherapy & Nuclear Medicine, Docrates Cancer Center, Saukonpaadenranta 2, 00180 Helsinki, Finland.
authors.forename: Kalevi
authors.identifier: 0000-0002-5194-746X
authors.initials: K
authors.lastname: Kairemo
authors.affiliation: Department of Molecular Radiotherapy & Nuclear Medicine, Docrates Cancer Center, Saukonpaadenranta 2, 00180 Helsinki, Finland.
authors.forename: Nigora
authors.identifier: 0000-0002-8074-7870
authors.initials: N
authors.lastname: Rasulova
authors.affiliation: Department of Radiology, Docrates Cancer Center, Saukonpaadenranta 2, 00180 Helsinki, Finland.
authors.forename: Kaarina
authors.initials: K
authors.lastname: Partanen
authors.affiliation: Department of Medical Oncology and Clinical Radiotherapy, Docrates Cancer Center, Saukonpaadenranta 2, 00180 Helsinki, Finland.
authors.forename: Timo
authors.initials: T
authors.lastname: Joensuu
mesh_terms: D000368:Aged; D002264:Carboxylic Acids; D003503:Cyclobutanes; D003952:Diagnostic Imaging; D006801:Humans; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000000981:diagnostic imaging* / Q000473:pathology; D049268:Positron-Emission Tomography; D017430:Prostate-Specific Antigen / Q000302:isolation & purification; D011471:Prostatic Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D011859:Radiography; D019275:Radiopharmaceuticals
chemical_list: D002264:Carboxylic Acids; D003503:Cyclobutanes; D019275:Radiopharmaceuticals; C117460:fluciclovine F-18; D017430:Prostate-Specific Antigen