title: Lymph-Node Ratio in Patients with Cutaneous Melanoma: A Multi-Institution Prognostic Study.
abstract: BACKGROUND
  Lymph node ratio (LNR)-the number of metastatic lymph nodes (LNs) over the number of excised LNs after lymphadenectomy-is a prognostic factor for many solid tumors, but controversies still exist for skin melanoma. We investigated the prognostic relevance of LNR in melanoma patients and formulated a proposal for considering the LNR in the current American Joint Committee on Cancer (AJCC) N staging system.
  
  
  METHODS
  Retrospective data of 2,526 melanoma patients with LN metastasis from nine Italian institutions were collected in a multicenter database. The prognostic value of the LNR (categorized as A, ≤0.1; B, 0.11-0.25; and C, >0.25) was assessed by multivariable survival analysis.
  
  
  RESULTS
  LNR was a significant independent prognostic factor for melanoma-specific survival (LNR B vs. A: hazard ratio [HR] 1.47, 95 % CI 1.16-1.87, p = 0.002; LNR C vs. A: HR 1.84, 95 % CI 1.29-2.61, p = 0.001). The LNR had prognostic value in patients with AJCC N1a (one positive LN after sentinel LN biopsy [SLNB], HR 2.33, 95 % CI 1.49-3.63, p < 0.001) and N2a (two to three positive LNs after SLNB, HR 1.62, 95 % CI 1.09-2.40, p = 0.016) substages, but not in those with N1b (one clinically positive LN, p = 0.765), N2b (two to three clinically positive LNs, p = 0.165), and N3 (≥ four positive LNs, p = 0.084) substages.
  
  
  CONCLUSIONS
  The LNR is a prognostic factor in melanoma patients with one (AJCC N1a) and two to three (AJCC N2a) positive LNs after SLNB. This easy-to-obtain parameter should be considered for the staging of melanoma patients with LN metastasis, along with the number of positive LNs.
authors.affiliation: Surgery Branch, Department of Surgery Oncology and Gastroenterology, University of Padova, Padua, Italy.
authors.forename: Pasquali
authors.initials: P
authors.lastname: Sandro
authors.forename: Maurichi
authors.initials: M
authors.lastname: Andrea
authors.forename: Mozzillo
authors.initials: M
authors.lastname: Nicola
authors.forename: Mocellin
authors.initials: M
authors.lastname: Simone
authors.forename: Macripò
authors.initials: M
authors.lastname: Giuseppe
authors.forename: Borgognoni
authors.initials: B
authors.lastname: Lorenzo
authors.forename: Solari
authors.initials: S
authors.lastname: Nicola
authors.forename: Piazzalunga
authors.initials: P
authors.lastname: Dario
authors.forename: Mascheroni
authors.initials: M
authors.lastname: Luigi
authors.forename: Giudice
authors.initials: G
authors.lastname: Giuseppe
authors.forename: Patuzzo
authors.initials: P
authors.lastname: Roberto
authors.forename: Caracò
authors.initials: C
authors.lastname: Corrado
authors.forename: Ribero
authors.initials: R
authors.lastname: Simone
authors.forename: Marone
authors.initials: M
authors.lastname: Ugo
authors.forename: Santinami
authors.initials: S
authors.lastname: Mario
authors.forename: Rossi Carlo
authors.initials: RC
authors.lastname: Riccardo
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008197:Lymph Node Excision / Q000401:mortality*; D008198:Lymph Nodes / Q000473:pathology* / Q000601:surgery; D008207:Lymphatic Metastasis; D008297:Male; D008545:Melanoma / Q000401:mortality* / Q000473:pathology* / Q000601:surgery; D008875:Middle Aged; D009367:Neoplasm Staging; D011379:Prognosis; D012189:Retrospective Studies; D012878:Skin Neoplasms; D015996:Survival Rate; D000096142:Cutaneous Malignant Melanoma