title: Risk Factors Predicting Positive Margins at Primary Wide Local Excision of Cutaneous Melanoma.
abstract: BACKGROUND
  A small percentage of patients will have positive histological margins after primary wide local excision (WLE) of cutaneous melanoma (CM). Risk factors that predict marginal involvement at WLE remain unclear.
  
  
  OBJECTIVE
  To identify risk factors associated with positive margins after WLE of CM.
  
  
  METHODS
  A retrospective review of patients treated at a single institution for CM with sentinel lymph node biopsy from 1997 to 2011 was conducted.
  
  
  RESULTS
  Positive margins occurred in 6% of patients. Patients with positive margins were older (72.4 vs 60.7, p < .001), had thicker tumors (3.6 vs 1.9 mm, p < .001), and often involved the head and neck region (p < .001). Patients with positive margins at WLE had positive margins on initial biopsy (p = .012) and a higher rate of a melanoma in situ component on initial biopsy (24% vs 11%, p = .02). The 5-year local recurrence rate was significantly different between those with positive and negative margins at WLE (16.0% vs 6.9%; p = .047).
  
  
  CONCLUSIONS
  Positive margins after WLE are uncommon. When a patient has multiple risk factors for positive margins at WLE, histologically clear margins should be obtained through mapped serial excision or Mohs micrographic surgery.
authors.affiliation: *Department of Dermatology, Mayo Clinic, Scottsdale, Arizona; †Division of Dermatology, LewisGale Hospital Montgomery, Blacksburg, Virginia; ‡Section of Biostatistics, Mayo Clinic, Scottsdale, Arizona; §Department of Surgery, Section of Surgical Oncology, Mayo Clinic, Phoenix, Arizona.
authors.forename: Aaron R
authors.initials: AR
authors.lastname: Mangold
authors.forename: Ryan
authors.initials: R
authors.lastname: Skinner
authors.forename: Amylou C
authors.initials: AC
authors.lastname: Dueck
authors.forename: Aleksandar
authors.initials: A
authors.lastname: Sekulic
authors.forename: Barbara A
authors.initials: BA
authors.lastname: Pockaj
mesh_terms: D000367:Age Factors; D000368:Aged; D001706:Biopsy; D005260:Female; D006801:Humans; D008297:Male; D008545:Melanoma / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery*; D008875:Middle Aged; D015580:Mohs Surgery; D009364:Neoplasm Recurrence, Local / Q000473:pathology; D018365:Neoplasm, Residual / Q000473:pathology*; D012189:Retrospective Studies; D012307:Risk Factors; D021701:Sentinel Lymph Node Biopsy; D012878:Skin Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery*