title: Analysis of sentinel node positivity in primary cutaneous melanoma: an 8-year single institution experience.
abstract: BACKGROUND
  Sentinel lymph node biopsy (SLNB) is a standard method for determining the pathologic status of the regional lymph nodes.
  
  
  OBJECTIVE
  The aim of our study was to determine the incidence and clinicopathologic factors predictive of SLN positivity, and to evaluate the prognostic importance of SLNB in patients with cutaneous melanoma.
  
  
  METHODS
  We performed a retrospective analysis of a prospectively maintained database of all patients who underwent SLNB for primary melanoma at our institution from 2005 to 2012. Statistical analysis was performed using χ2and Fischer exact test.
  
  
  RESULTS
  In total, 318 patients underwent SLNB, of which 65 were for thin melanoma (≤1 mm). There were 36 positive SLNB, 278 negative SLNB and in four cases the SLN was not located. The incidence rate for SLNB was 11.3% overall and 1.5% in thin melanomas alone. Statistical analysis identified Breslow thickness >1 mm (P = 0.006), Clark level ≥ IV (P = 0.004) and age <75 years (P = 0.035) as the strongest predictors of SLN positivity. Our overall false negativity rate was 20% (9/45) with one case of false-negative SLNB in thin melanomas.
  
  
  CONCLUSIONS
  Breslow thickness of the primary tumour remains the strongest predictor of SLN positivity. Our findings point to a possible limited role for SLNB in thin melanoma due to its low positivity rate, associated false-negative rate and related morbidity.
authors.affiliation: Department of Plastic and Reconstructive Surgery, Galway University Hospital, Galway, Ireland. kennethjoyce1@gmail.com.
authors.forename: K M
authors.initials: KM
authors.lastname: Joyce
authors.affiliation: Department of Plastic and Reconstructive Surgery, Galway University Hospital, Galway, Ireland.
authors.forename: N M
authors.initials: NM
authors.lastname: McInerney
authors.affiliation: Department of Plastic and Reconstructive Surgery, Galway University Hospital, Galway, Ireland.
authors.forename: R P
authors.initials: RP
authors.lastname: Piggott
authors.affiliation: Department of Plastic and Reconstructive Surgery, Galway University Hospital, Galway, Ireland.
authors.forename: F
authors.initials: F
authors.lastname: Martin
authors.affiliation: Department of Plastic and Reconstructive Surgery, Galway University Hospital, Galway, Ireland.
authors.forename: D M
authors.initials: DM
authors.lastname: Jones
authors.affiliation: Department of Plastic and Reconstructive Surgery, Galway University Hospital, Galway, Ireland.
authors.forename: A J
authors.initials: AJ
authors.lastname: Hussey
authors.affiliation: Department of Surgery, Clinical Science Institute, Galway University Hospital, Galway, Ireland.
authors.forename: M J
authors.initials: MJ
authors.lastname: Kerin
authors.affiliation: Department of Plastic and Reconstructive Surgery, Galway University Hospital, Galway, Ireland.
authors.forename: J L
authors.initials: JL
authors.lastname: Kelly
authors.affiliation: Department of Plastic and Reconstructive Surgery, Galway University Hospital, Galway, Ireland.
authors.forename: P J
authors.initials: PJ
authors.lastname: Regan
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D008297:Male; D008545:Melanoma / Q000601:surgery* / Q000628:therapy; D008875:Middle Aged; D011379:Prognosis; D012189:Retrospective Studies; D021701:Sentinel Lymph Node Biopsy / Q000379:methods*; D012878:Skin Neoplasms / Q000601:surgery* / Q000628:therapy; D013997:Time Factors; D055815:Young Adult; D000096142:Cutaneous Malignant Melanoma
keywords: Melanoma; Metastasis; Sentinel node