title: The importance of applying a sentinel lymph node mapping algorithm in endometrial cancer staging: beyond removal of blue nodes.
abstract: OBJECTIVE
  To determine the false-negative rate of a surgical sentinel lymph node (SLN) mapping algorithm that incorporates more than just removing SLNs in detecting metastatic endometrial cancer.
  
  
  METHODS
  A prospective database of all patients who underwent lymphatic mapping for endometrial cancer was reviewed. Cervical injection of blue dye was used in all cases. The surgical algorithm is as follows: 1) peritoneal and serosal evaluation and washings; 2) retroperitoneal evaluation including excision of all mapped SLNs and suspicious nodes regardless of mapping; and 3) if there is no mapping on a hemi-pelvis, a side-specific pelvic, common iliac, and interiliac lymph node dissection (LND) is performed. Paraaortic LND is performed at the attendings' discretion. The algorithm was retrospectively applied.
  
  
  RESULTS
  From 9/2005 to 4/2011, 498 patients received a blue dye cervical injection for SLN mapping. At least one LN was removed in 95% of cases (474/498); at least one SLN was identified in 81% (401/498). SLN correctly diagnosed 40/47 patients with nodal metastases who had at least one SLN mapped, resulting in a 15% false-negative rate. After applying the algorithm, the false-negative rate dropped to 2%. Only one patient, whose LN spread would not have been caught by the algorithm, had an isolated positive right paraaortic LN with a negative ipsilateral SLN and pelvic LND.
  
  
  CONCLUSIONS
  Satisfactory SLN mapping in endometrial cancer requires adherence to a surgical SLN algorithm and goes beyond just the removal of blue SLNs. Removal of any suspicious node along with side-specific lymphadenectomy for failed mapping are an integral part of this algorithm. Further validation of the false-negative rate of this algorithm is necessary.
authors.affiliation: Gynecology Service, Department of Surgery, Memorial Sloan-Kettering Cancer Center, New York, NY 10065, USA.
authors.forename: Joyce N
authors.initials: JN
authors.lastname: Barlin
authors.forename: Fady
authors.initials: F
authors.lastname: Khoury-Collado
authors.forename: Christine H
authors.initials: CH
authors.lastname: Kim
authors.forename: Mario M
authors.initials: MM
authors.lastname: Leitao
authors.forename: Dennis S
authors.initials: DS
authors.lastname: Chi
authors.forename: Yukio
authors.initials: Y
authors.lastname: Sonoda
authors.forename: Kaled
authors.initials: K
authors.lastname: Alektiar
authors.forename: Deborah F
authors.initials: DF
authors.lastname: DeLair
authors.forename: Richard R
authors.initials: RR
authors.lastname: Barakat
authors.forename: Nadeem R
authors.initials: NR
authors.lastname: Abu-Rustum
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000465:Algorithms; D016208:Databases, Factual; D016889:Endometrial Neoplasms / Q000473:pathology* / Q000601:surgery; D005188:False Negative Reactions; D005260:Female; D006801:Humans; D008197:Lymph Node Excision; D008198:Lymph Nodes / Q000473:pathology* / Q000601:surgery; D008751:Methylene Blue; D008875:Middle Aged; D021701:Sentinel Lymph Node Biopsy / Q000379:methods*; D013194:Staining and Labeling / Q000379:methods
chemical_list: D008751:Methylene Blue