title: Detection of recurrent prostate cancer lesions before salvage lymphadenectomy is more accurate with (68)Ga-PSMA-HBED-CC than with (18)F-Fluoroethylcholine PET/CT.
abstract: OBJECTIVE
  [(68)Ga]PSMA-HBED-CC ((68)Ga-PSMA) is a novel and promising tracer for highly sensitive combined integrated positron emission tomography and X-ray computed tomography (PET/CT) diagnosis of recurrent prostate cancer (PCA). Our aim was to assess the sensitivity, specificity, positive and negative predictive value (PPV/NPV), and accuracy per lesion, as well as the positive predictive value per patient of (68)Ga-PSMA PET/CT using post-lymphadenectomy histology as a standard, and to compare these values to those obtained in a patient collective scanned using (18)F-Fluoroethylcholine ((18)FEC) PET/CT.
  
  
  METHODS
  Thirty eight patients had (18)FEC and 28 patients had (68)Ga-PSMA. We performed a pelvic and/or retroperitoneal lymphadenectomy, if necessary supplemented by resection of locally recurrent lesions in accordance with imaging results.
  
  
  RESULTS
  In 30/38 (18)FEC and 23/28 (68)Ga-PSMA patients ≥1 focus of PCA was identified in postsurgical histology, leading to a per-patient PPV of 78.9 % for (18)FEC and 82.1 % for (68)Ga-PSMA. In (18)FEC and (68)Ga-PSMA patients, a total of 378 and 308 lymph nodes and local lesions were removed, respectively. For (18)FEC and (68)for Ga-PSMA, the respective sensitivity (95 % confidence interval) was 71.2 % (64.5-79.6 %) and 86.9 % (75.8-94.2 %), specificity was 86.9 % (82.3-90.6 % ) and 93.1 % (89.2-95.9 %), PPV was 67.3 % (57.7-75.9 %) and 75.7 % (64.0-98.5 %), NPV was 88.8 % (84.4-92.3 %) and 96.6 % (93.5-98.5 %), and accuracy was 82.5 % (78.3-86.8 %) and 91.9 % (88.7 %-95.1 %).
  
  
  CONCLUSIONS
  In the present series Ga-PSMA PET/CT shows a better performance than FEC PET/CT with a significantly higher NPV and accuracy for the detection of locoregional recurrent and/or metastatic lesions prior to salvage lymphadenectomy.
authors.affiliation: Department of Urology, RWTH University Hospital Aachen, Aachen, Germany. david.pfister@uk-koeln.de.|Department of Urology, University Hospital Cologne, Kerpener Strasse 62, 50937, Köln, Cologne, Germany. david.pfister@uk-koeln.de.
authors.forename: David
authors.initials: D
authors.lastname: Pfister
authors.affiliation: Department of Urology, RWTH University Hospital Aachen, Aachen, Germany.|Department of Urology, University Hospital Cologne, Kerpener Strasse 62, 50937, Köln, Cologne, Germany.
authors.forename: Daniel
authors.initials: D
authors.lastname: Porres
authors.affiliation: Department of Urology, RWTH University Hospital Aachen, Aachen, Germany.|Department of Urology, University Hospital Cologne, Kerpener Strasse 62, 50937, Köln, Cologne, Germany.
authors.forename: Axel
authors.initials: A
authors.lastname: Heidenreich
authors.affiliation: Department of Urology, RWTH University Hospital Aachen, Aachen, Germany.
authors.forename: Isabel
authors.initials: I
authors.lastname: Heidegger
authors.affiliation: Department of Pathology, RWTH University Hospital Aachen, Aachen, Germany.
authors.forename: Ruth
authors.initials: R
authors.lastname: Knuechel
authors.affiliation: Department of Pathology, RWTH University Hospital Aachen, Aachen, Germany.
authors.forename: Florian
authors.initials: F
authors.lastname: Steib
authors.affiliation: Department of Nuclear Medicine, RWTH University Hospital Aachen, Aachen, Germany.
authors.forename: Florian F
authors.initials: FF
authors.lastname: Behrendt
authors.affiliation: Department of Nuclear Medicine, RWTH University Hospital Aachen, Aachen, Germany.
authors.forename: Frederik A
authors.initials: FA
authors.lastname: Verburg
mesh_terms: D000368:Aged; D002794:Choline / Q000031:analogs & derivatives*; D004492:Edetic Acid / Q000031:analogs & derivatives*; D005709:Gallium Isotopes; D005710:Gallium Radioisotopes; D006801:Humans; D008197:Lymph Node Excision; D008297:Male; D008875:Middle Aged; D009842:Oligopeptides; D000072078:Positron Emission Tomography Computed Tomography / Q000379:methods*; D011471:Prostatic Neoplasms / Q000000981:diagnostic imaging* / Q000601:surgery*; D012008:Recurrence; D012189:Retrospective Studies; D016879:Salvage Therapy; D012680:Sensitivity and Specificity
chemical_list: D005709:Gallium Isotopes; D005710:Gallium Radioisotopes; D009842:Oligopeptides; C000718244:gallium 68 PSMA-11; C448902:fluoroethylcholine; D004492:Edetic Acid; D002794:Choline
keywords: F-18-Fluoroethycholine PET/CT; Ga-68-PSMA PET/CT; Histology; Prostate cancer; Salvage lymphadenectomy