title: Prostate-specific membrane antigen-based imaging in prostate cancer: impact on clinical decision making process.
abstract: BACKGROUND
  There is an ongoing need for an accurate imaging modality which can be used for staging purposes, metastatic evaluation, predicting biologic aggresiveness and investigating recurrent disease in prostate cancer. Prostate specific membrane antigen, given its favorable molecular characteristics, holds a promise as an ideal target for prostate cancer-specific nuclear imaging. In this study, we evaluated our initial results of PSMA based PET/CT imaging in prostate cancer.
  
  
  METHODS
  A total of 22 patients with a median age and serum PSA level of 68 years and 4.15 ng/ml, respectively underwent Ga-68 PSMA PET/CT in our hospital between Februrary and August 2014. Their charts were retrospectively reviewed in order to document the clinical characteristics, the indications for and the results of PSMA based imaging and the impact of Ga-68 PSMA PET/CT findings on disease management.
  
  
  RESULTS
  The most common indications were rising PSA after local ± adjuvant treatment followed by staging and metastatic evaluation before definitive or salvage treatment. All except 2 patients had prostatic ± extraprostatic PSMA positive lesions. For those who had a positive result; treatment strategies were tailored accordingly. Above the PSA level of 2 ng/ml, none of the PSMA based nuclear imaging studies revealed negative results.
  
  
  CONCLUSIONS
  PSMA based nuclear imaging has significantly impacted our way of handling patients with prostate cancer. Its preliminary performance in different clinical scenarios and ability to detect lesions even in low PSA values seems fairly promising and deserves to be supplemented with further clinical studies.
authors.affiliation: Koc University, School of Medicine, Department of Nuclear Medicine and Molecular Imaging, Istanbul, Turkey; VKF American Hospital, Department of Nuclear Medicine and Molecular Imaging, Istanbul, Turkey.
authors.forename: Mehmet Onur
authors.initials: MO
authors.lastname: Demirkol
authors.forename: Ömer
authors.initials: Ö
authors.lastname: Acar
authors.forename: Burcu
authors.initials: B
authors.lastname: Uçar
authors.forename: Sultan Rana
authors.initials: SR
authors.lastname: Ramazanoğlu
authors.forename: Yeşim
authors.initials: Y
authors.lastname: Sağlıcan
authors.forename: Tarık
authors.initials: T
authors.lastname: Esen
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000954:Antigens, Surface / Q000032:analysis* / Q000378:metabolism; D005708:Gallium; D043425:Glutamate Carboxypeptidase II / Q000032:analysis* / Q000378:metabolism; D006801:Humans; D007610:Kallikreins / Q000097:blood; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging / Q000379:methods; D009367:Neoplasm Staging; D049268:Positron-Emission Tomography / Q000379:methods; D017430:Prostate-Specific Antigen / Q000097:blood; D011471:Prostatic Neoplasms / Q000097:blood / Q000175:diagnosis* / Q000378:metabolism; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed / Q000379:methods
chemical_list: D000954:Antigens, Surface; D005708:Gallium; C473848:FOLH1 protein, human; D043425:Glutamate Carboxypeptidase II; C549870:KLK3 protein, human; D007610:Kallikreins; D017430:Prostate-Specific Antigen
keywords: cancer; ligand; nuclear imaging; prostate