Stratifying SLN incidence in intermediate thickness melanoma patients

Am J Surg. 2018 Apr;215(4):699-706. doi: 10.1016/j.amjsurg.2017.12.009. Epub 2017 Dec 14.


Background: Guidelines for melanoma recommend sentinel lymph node biopsy (SLNB) in patients with melanomas ≥1 mm thickness. Recent single institution studies have found tumors <1.5 mm a low-risk group for positive SLNB.

Methods: A retrospective review of the Sentinel Lymph Node Working Group multicenter database identified patients with intermediate thickness melanoma (1.01-4.00 mm) who had SLNB, and assessed predictors for positive SLNB.

Results: 3460 patients were analyzed, 584 (17%) had a positive SLNB. Univariate factors associated with a positive SLNB included age <60 (p < .001), tumor on the trunk/lower extremity (p < .001), Breslow depth ≥2 mm (p < .001), ulceration (p < .001), mitotic rate ≥1/mm2 (p = .01), and microsatellitosis (p < .001). Multivariate analysis revealed age, location, and Breslow depth as significant predictors. Patients ≥75 with lesions 1.01-1.49 mm on the head/neck/upper extremity and 1.5-1.99 mm without high-risk features had <5% risk of SLN positivity.

Conclusions: Intermediate thickness melanoma has significant heterogeneity of SLNB positivity. Low-risk subgroups can be found among older patients in the absence of high-risk features.

Publication types

  • Multicenter Study

MeSH terms

  • Aged
  • Databases, Factual
  • Female
  • Humans
  • Incidence
  • Lymphatic Metastasis / pathology*
  • Male
  • Melanoma / pathology*
  • Middle Aged
  • Retrospective Studies
  • Risk Factors
  • Sentinel Lymph Node / pathology*
  • Sentinel Lymph Node Biopsy
  • Skin Neoplasms / pathology*