title: Detection Efficacy of Hybrid68Ga-PSMA Ligand PET/CT in Prostate Cancer Patients with Biochemical Recurrence After Primary Radiation Therapy Defined by Phoenix Criteria.
abstract: The aim of this retrospective study was to evaluate the detection rate of Glu-NH-CO-NH-Lys-(Ahx)-[68Ga(HBED-CC)] (68Ga-PSMA ligand; PSMA is prostate-specific membrane antigen) PET/CT in patients with biochemical recurrent prostate cancer defined by Phoenix criteria after external-beam radiotherapy or brachytherapy as primary treatment.Methods:One hundred eighteen patients with a median prostate-specific antigen (PSA) of 6.4 ng/mL (range, 2.2-158.4 ng/mL; interquartile range, 4.2-10.2 ng/mL) were finally eligible for this retrospective analysis. Seventy-seven and 41 patients had been treated by external-beam radiotherapy or brachytherapy, respectively. Of the 118 patients, 45 were receiving androgen-deprivation therapy (ADT) within at least 6 mo before the PET/CT. The detection rates were stratified by PSA. The influence of primary Gleason score and ADT was assessed. Relationships between SUV and clinical as well as pathologic features in patients with positive findings were analyzed using univariate and multivariable linear regression models.Results:One hundred seven of 118 patients (90.7%) showed pathologic findings indicative for tumor recurrence in68Ga-PSMA ligand PET/CT. The detection rates were 81.8% (36/44), 95.3% (41/43), and 96.8% (30/31) for PSA of 2 to <5, 5 to <10, and ≥10 ng/mL, respectively (P= 0.0377).68Ga-PSMA ligand PET/CT indicated local recurrence in 68 of 107 patients (63.5%), distant lesions in 64 of 107 patients (59.8%), and local recurrence as well as distant lesions in 25 of 107 patients (23.4%). The detection rate was significantly higher in patients with ADT (97.7%) versus without ADT (86.3%,P= 0.0381), but independent from primary Gleason score ≥ 8 (92.0%) versus ≤ 7 (90.2%,P= 0.6346). SUVmaxand SUVmeanwere significantly associated with PSA and ADT (P= 0.018 and 0.004 for SUVmax, respectively;P= 0.025 and 0.007 for SUVmean, respectively).Conclusion:68Ga-PSMA ligand PET/CT demonstrates high detection rates in patients with biochemical recurrence of prostate cancer after primary radiation therapy. The detection rate was positively associated to increasing PSA as well as concomitant ADT.68Ga-PSMA ligand PET/CT enables discrimination of local versus metastatic disease and thus might have a crucial impact on further clinical management. A major limitation of this study is the lack of histopathologic proof in most patients.
authors.affiliation: Department of Nuclear Medicine, Klinikum Rechts der Isar, Technical University of Munich, Munich, Germany ingo.einspieler@tum.de.|Department of Radiology, Klinikum Rechts der Isar, Technical University of Munich, Munich, Germany.
authors.forename: Ingo
authors.initials: I
authors.lastname: Einspieler
authors.affiliation: Department of Nuclear Medicine, Klinikum Rechts der Isar, Technical University of Munich, Munich, Germany.
authors.forename: Isabel
authors.initials: I
authors.lastname: Rauscher
authors.affiliation: Department of Urology, Klinikum Rechts der Isar, Technical University of Munich, Munich, Germany.
authors.forename: Charlotte
authors.initials: C
authors.lastname: Düwel
authors.affiliation: Department of Nuclear Medicine, Klinikum Rechts der Isar, Technical University of Munich, Munich, Germany.
authors.forename: Markus
authors.initials: M
authors.lastname: Krönke
authors.affiliation: Department of Nuclear Medicine, Klinikum Rechts der Isar, Technical University of Munich, Munich, Germany.
authors.forename: Christoph
authors.initials: C
authors.lastname: Rischpler
authors.affiliation: Department of Radiation Oncology, Klinikum Rechts der Isar, Technical University of Munich, Munich, Germany.
authors.forename: Gregor
authors.initials: G
authors.lastname: Habl
authors.affiliation: Department of Radiation Oncology, Klinikum Rechts der Isar, Technical University of Munich, Munich, Germany.
authors.forename: Sabrina
authors.initials: S
authors.lastname: Dewes
authors.affiliation: Institute of Medical Statistics and Epidemiology, Klinikum Rechts der Isar, Technical University of Munich, Munich, Germany.
authors.forename: Armin
authors.initials: A
authors.lastname: Ott
authors.affiliation: Pharmaceutical Radiochemistry, Technical University of Munich, Garching, Germany; and.
authors.forename: Hans-Jürgen
authors.initials: HJ
authors.lastname: Wester
authors.affiliation: Department of Nuclear Medicine, Klinikum Rechts der Isar, Technical University of Munich, Munich, Germany.
authors.forename: Markus
authors.initials: M
authors.lastname: Schwaiger
authors.affiliation: Department of Urology, Klinikum Rechts der Isar, Technical University of Munich, Munich, Germany.
authors.forename: Tobias
authors.initials: T
authors.lastname: Maurer
authors.affiliation: Department of Nuclear Medicine, Klinikum Rechts der Isar, Technical University of Munich, Munich, Germany.|Department of Molecular and Medical Pharmacology, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California.
authors.forename: Matthias
authors.initials: M
authors.lastname: Eiber
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000097:blood; D004492:Edetic Acid / Q000031:analogs & derivatives; D005709:Gallium Isotopes; D005710:Gallium Radioisotopes; D006801:Humans; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000097:blood / Q000000981:diagnostic imaging* / Q000517:prevention & control; D015588:Observer Variation; D009842:Oligopeptides; D009942:Organometallic Compounds; D000072078:Positron Emission Tomography Computed Tomography / Q000379:methods* / Q000592:standards; D017410:Practice Guidelines as Topic; D017430:Prostate-Specific Antigen / Q000097:blood*; D011471:Prostatic Neoplasms / Q000097:blood / Q000000981:diagnostic imaging* / Q000532:radiotherapy*; D019275:Radiopharmaceuticals; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D016896:Treatment Outcome
chemical_list: D014408:Biomarkers, Tumor; D005709:Gallium Isotopes; D005710:Gallium Radioisotopes; D009842:Oligopeptides; D009942:Organometallic Compounds; D019275:Radiopharmaceuticals; C000718244:gallium 68 PSMA-11; D004492:Edetic Acid; D017430:Prostate-Specific Antigen
keywords: EBRT; PET/CT; PSMA ligand; brachytherapy; prostate cancer