title: Value of111In-prostate-specific membrane antigen (PSMA)-radioguided surgery for salvage lymphadenectomy in recurrent prostate cancer: correlation with histopathology and clinical follow-up.
abstract: To evaluate the use of111In-labelled prostate-specific membrane antigen (PSMA)-I&T-based radioguided surgery (111In-PSMA-RGS) for salvage surgery in recurrent prostate cancer (PCa) using comparison of intra-operative gamma probe measurements with histopathological results of dissected specimens. In addition, to determine the success of111In-PSMA-RGS with regard to postoperative prostate-specific antigen (PSA) responses, PCa-specific treatment-free survival rates and postoperative complication rates.
  
  
  
  A total of 31 consecutive patients with localized recurrent PCa undergoing salvage surgery with PSMA-targeted radioguided surgery using a111In-labelled PSMA ligand between April 2014 and July 2015 were retrospectively included in this study. The preoperative (interquartile range; range) median PSA level was 1.3 (0.57-2.53 ng/mL; 0.2-13.9 ng/mL). Results of ex vivo radioactivity rating (positive vs negative) of resected tissue specimens were compared with findings of postoperative histological analysis. Best PSA response without additional treatment was determined after111In-PSMA-RGS, and salvage-surgery-related postoperative complications and PCa-specific additional treatments were recorded.
  
  
  
  In 30/31 patients,111In-PSMA-RGS allowed intra-operative identification of metastatic lesions. In total, 145 surgical specimens were removed and 51 showed metastatic involvement at histological analysis. According to111In-PSMA-RGS ex vivo measurements, 48 specimens were correctly classified as metastatic and 87 as cancer-free, four were false-negative and six were false-positive compared with histological evaluation. Follow-up information was available for 30/31 patients. PSA declines of >50% and >90% were observed in 23/30 patients and in 16/30 patients, respectively. In 18/30 patients, a PSA decline to <0.2 ng/mL was observed. In 10/30 patients further PCa-specific treatment was given after a median (range) of 125 (48-454) days post-111In-PSMA-RGS. The remaining 20 patients remained treatment-free at a median (range) follow-up of 337 (81-591) days. Of 30 patients, 10 presented with surgery-related complications (Clavien-Dindo grade 1, n = 6, Clavien-Dindo grade 3b, n = 4).
  
  
  
  111In-PSMA-RGS proved to be of high value for intra-operative detection of even small metastatic lesions in patients with PCa scheduled for salvage lymphadenectomy. It allows the exact localization and resection of metastatic tissue during111In-PSMA-RGS and is therefore anticipated to have a beneficial influence on further disease progression; however, identification of suitable patients on the basis of PSMA-positron-emission tomography imaging as well as clinical variables is essential for satisfactory results to be obtained.
authors.affiliation: Department of Nuclear Medicine, Technical University of Munich, Klinikum rechts der Isar, Munich, Germany.
authors.forename: Isabel
authors.initials: I
authors.lastname: Rauscher
authors.affiliation: Department of Urology, Technical University of Munich, Klinikum rechts der Isar, Munich, Germany.
authors.forename: Charlotte
authors.initials: C
authors.lastname: Düwel
authors.affiliation: Institute of Pharmaceutical Radiochemistry, Technical University of Munich, Garching, Germany.
authors.forename: Martina
authors.initials: M
authors.lastname: Wirtz
authors.affiliation: Institute of Pharmaceutical Radiochemistry, Technical University of Munich, Garching, Germany.
authors.forename: Margret
authors.initials: M
authors.lastname: Schottelius
authors.affiliation: Institute of Pharmaceutical Radiochemistry, Technical University of Munich, Garching, Germany.
authors.forename: Hans-Jürgen
authors.initials: HJ
authors.lastname: Wester
authors.affiliation: Department of Pathology, Technical University of Munich, Klinikum rechts der Isar, Munich, Germany.
authors.forename: Kristina
authors.initials: K
authors.lastname: Schwamborn
authors.affiliation: Institute of Medical Statistics and Epidemiology, Technical University of Munich, Klinikum rechts der Isar, Munich, Germany.
authors.forename: Bernhard
authors.initials: B
authors.lastname: Haller
authors.affiliation: Department of Nuclear Medicine, Technical University of Munich, Klinikum rechts der Isar, Munich, Germany.
authors.forename: Markus
authors.initials: M
authors.lastname: Schwaiger
authors.affiliation: Department of Urology, Technical University of Munich, Klinikum rechts der Isar, Munich, Germany.
authors.forename: Jürgen E
authors.initials: JE
authors.lastname: Gschwend
authors.affiliation: Department of Nuclear Medicine, Technical University of Munich, Klinikum rechts der Isar, Munich, Germany.
authors.forename: Matthias
authors.initials: M
authors.lastname: Eiber
authors.affiliation: Department of Urology, Technical University of Munich, Klinikum rechts der Isar, Munich, Germany.
authors.forename: Tobias
authors.initials: T
authors.lastname: Maurer
mesh_terms: D000368:Aged; D005500:Follow-Up Studies; D006801:Humans; D008197:Lymph Node Excision; D008198:Lymph Nodes / Q000473:pathology*; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local; D017430:Prostate-Specific Antigen / Q000097:blood*; D011471:Prostatic Neoplasms / Q000097:blood / Q000473:pathology* / Q000601:surgery; D019275:Radiopharmaceuticals; D012189:Retrospective Studies; D016879:Salvage Therapy / Q000379:methods*; D025321:Surgery, Computer-Assisted; D015996:Survival Rate
chemical_list: D019275:Radiopharmaceuticals; D017430:Prostate-Specific Antigen
keywords: 
  PSMA
  ; #PCSM; #ProstateCancer; biochemical recurrence; pelvic lymphadenectomy; radioguided surgery; salvage surgery