title: Rotterdam Criteria for sentinel node (SN) tumor burden and the accuracy of ultrasound (US)-guided fine-needle aspiration cytology (FNAC): can US-guided FNAC replace SN staging in patients with melanoma?
abstract: OBJECTIVE
  Sentinel node (SN) status is the most important prognostic factor for overall survival (OS) for patients with stage I/II melanoma, and the role of the SN procedure as a staging procedure has long been established. However, a less invasive procedure, such as ultrasound (US) -guided fine-needle aspiration cytology (FNAC), would be preferred. The aim of this study was to evaluate the accuracy of US-guided FNAC and compare the results with histology after SN surgery was performed in all patients.
  
  
  METHODS
  Four hundred consecutive patients who underwent lymphoscintigraphy subsequently underwent a US examination before the SN procedure. When the US examination showed a suspicious or malignant pattern, patients underwent an FNAC. Median Breslow thickness was 1.8 mm; mean follow-up was 42 months (range, 4 to 82 months). We considered the US-guided FNAC positive if either US and/or FNAC were positive. If US was suggestive of abnormality, but FNAC was negative, the US-guided FNAC was considered negative.
  
  
  RESULTS
  US-guided FNAC identified 51 (65%) of 79 SN metastases. Specificity was 99% (317 of 321), with a positive predictive value of 93% and negative predictive value of 92%. SN-positive identification rate by US-guided FNAC increased from 40% in stage pT1a/b disease to 79% in stage pT4a/b disease. US-guided FNAC detected SN tumors more than 1.0 mm in 86% of cases, SN tumors of 0.1 to 1.0 mm in 46% of cases, and SN tumors less than 0.1 mm in 23% of cases. Estimated 5-year OS rates were 92% for patients with negative US-guided FNAC results and 51% for patients with positive results.
  
  
  CONCLUSIONS
  US-guided FNAC of SNs is highly accurate. Up to 65% of the patients with SN-positive results in our institution could have been spared an SN procedure.
authors.affiliation: Department of Dermatology, Charité, Humboldt University, Berlin, Germany. christiane.voit@t-online.de
authors.forename: Christiane A
authors.initials: CA
authors.lastname: Voit
authors.forename: Alexander C J
authors.initials: AC
authors.lastname: van Akkooi
authors.forename: Gregor
authors.initials: G
authors.lastname: Schäfer-Hesterberg
authors.forename: Alfred
authors.initials: A
authors.lastname: Schoengen
authors.forename: Paul I M
authors.initials: PI
authors.lastname: Schmitz
authors.forename: Wolfram
authors.initials: W
authors.lastname: Sterry
authors.forename: Alexander M M
authors.initials: AM
authors.lastname: Eggermont
mesh_terms: D044963:Biopsy, Fine-Needle / Q000379:methods*; D005260:Female; D006801:Humans; D008198:Lymph Nodes / Q000000981:diagnostic imaging / Q000473:pathology*; D008207:Lymphatic Metastasis; D008297:Male; D008545:Melanoma / Q000473:pathology*; D008875:Middle Aged; D009367:Neoplasm Staging / Q000379:methods*; D011446:Prospective Studies; D021701:Sentinel Lymph Node Biopsy; D012878:Skin Neoplasms / Q000473:pathology*; D047368:Tumor Burden; D014463:Ultrasonography