title: Utility of [11C]choline PET/CT in guiding lesion-targeted salvage therapies in patients with prostate cancer recurrence localized to a single lymph node at imaging: results from a pathologically validated series.
abstract: OBJECTIVE
  Positron emission tomography (PET)/computed tomography (CT) has been shown to be a valid tool in detecting lymph node (LN) metastases in men with biochemical recurrence after radical prostatectomy. We assessed its validity in detecting a single positive LN at pathologic examination in regard to an increasing interest in lesion-targeted salvage therapies.
  
  
  METHODS
  We included 46 patients with biochemical recurrence after radical prostatectomy and a single positive spot at [(11)C]choline PET/CT who underwent pelvic or pelvic and retroperitoneal LN dissection. The ability of [(11)C]choline PET/CT in identifying the exact positive LN was assessed with the positive predictive value (PPV) in the overall population and according to androgen deprivation therapy, prostate-specific antigen value, and site of PET/CT positivity.
  
  
  RESULTS
  Overall, 30 patients (65%) had positive LNs at pathologic examination. Of these, only 16 (35%) had pathologically confirmed metastases in the same lymphatic region and 11 (24%) had involvement of 1 single LN. Conversely, 28 patients had positive LNs in other areas and 8 had no evidence of metastases. The overall PPV of PET/CT was 34.8% and 23.9% when exact concordance was defined according to the lymphatic landing site and single positive LN, respectively. The PPV ranged from 33.3% to 44.4% and from 17.9% to 28.6%, in men with and without androgen deprivation therapy, respectively.
  
  
  CONCLUSIONS
  The PPV [(11)C]choline of PET/CT in correctly identifying patients with a single positive LN at salvage LN dissection is poor (24%). Therefore, extensive salvage treatment approaches are needed to maximize the chance of cure.
authors.affiliation: Department of Urology, Urological Research Institute, Vita-Salute University, San Raffaele Hospital, Milan, Italy.
authors.forename: Niccolò M
authors.initials: NM
authors.lastname: Passoni
authors.affiliation: Department of Urology, Urological Research Institute, Vita-Salute University, San Raffaele Hospital, Milan, Italy.
authors.forename: Nazareno
authors.initials: N
authors.lastname: Suardi
authors.affiliation: Department of Urology, Urological Research Institute, Vita-Salute University, San Raffaele Hospital, Milan, Italy.
authors.forename: Firas
authors.initials: F
authors.lastname: Abdollah
authors.affiliation: Department of Nuclear Medicine, Vita Salute University, San Raffaele Hospital, Milan, Italy.
authors.forename: Maria
authors.initials: M
authors.lastname: Picchio
authors.affiliation: Department of Nuclear Medicine, Vita Salute University, San Raffaele Hospital, Milan, Italy.
authors.forename: Giampiero
authors.initials: G
authors.lastname: Giovacchini
authors.affiliation: Center for Molecular Bioimaging, University of Milano-Bicocca, Milano, Italy.
authors.forename: Cristina
authors.initials: C
authors.lastname: Messa
authors.affiliation: Department of Pathology, Vita-Salute University, San Raffaele Hospital, Milan, Italy.
authors.forename: Massimo
authors.initials: M
authors.lastname: Freschi
authors.affiliation: Department of Urology, Urological Research Institute, Vita-Salute University, San Raffaele Hospital, Milan, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Montorsi
authors.affiliation: Department of Urology, Urological Research Institute, Vita-Salute University, San Raffaele Hospital, Milan, Italy. Electronic address: briganti.alberto@hsr.it.
authors.forename: Alberto
authors.initials: A
authors.lastname: Briganti
mesh_terms: D000368:Aged; D000726:Androgen Antagonists / Q000627:therapeutic use; D002250:Carbon Radioisotopes; D002794:Choline; D006801:Humans; D008197:Lymph Node Excision; D008198:Lymph Nodes / Q000000981:diagnostic imaging* / Q000601:surgery; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging / Q000379:methods; D009364:Neoplasm Recurrence, Local; D017063:Outcome Assessment, Health Care / Q000379:methods / Q000706:statistics & numerical data; D049268:Positron-Emission Tomography / Q000379:methods*; D011446:Prospective Studies; D017430:Prostate-Specific Antigen / Q000032:analysis; D011471:Prostatic Neoplasms / Q000175:diagnosis* / Q000628:therapy; D015203:Reproducibility of Results; D016879:Salvage Therapy; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D000726:Androgen Antagonists; D002250:Carbon Radioisotopes; D017430:Prostate-Specific Antigen; D002794:Choline
keywords: Lymph node dissection; PET/CT; Prostate cancer; Recurrence; Staging