title: Prognostic value of lymph node ratio in patients with advanced epithelial ovarian cancer.
abstract: OBJECTIVE
  Lymph node status is an established prognostic factor in epithelial ovarian cancer (EOC). Lymph node ratio (number of positive LN/number of resected LN) reflects both qualitative and quantitative lymph node spread as well as surgical effort and extent of disease. We evaluated whether LNR is a more precise prognostic factor than conventional lymph node status in patients with EOC.
  
  
  METHODS
  The present retrospective study includes 809 patients with EOC, who underwent primary cytoreductive surgery between 2000-2013. Clinico-pathological parameters and survival data were extracted from a prospectively maintained tumor registry database. The optimal cut-off point for LNR was calculated by using Martingale residuals. Survival analyses were calculated using Kaplan-Meier method and Cox regression models.
  
  
  RESULTS
  Lymphadenectomy was performed in 693 (85.7%) out of 809 patients. Median number of removed LN was 64 (IQR 25-75%: 39-84). LNR of 0.25 was identified as the optimal prognostic cut-off value. The estimated 5-year-OS rates were 69.3% for patients with node-negative EOC compared to 33.1% for patients with any lymph node metastasis (p<0.001). The estimated 5-year-OS rates were 42.5% for patients with LNR≤0.25, and 18.0% for patients with LNR>0.25 (p<0.001). Additionally in multivariate analysis LNR>0.25 was approved to be an independent prognostic factor for overall survival (adjusted HR 1.44, 95% CI 1.04-2.00; p=0.028).
  
  
  CONCLUSIONS
  LNR more precisely predicts overall survival than conventional lymph node status in EOC patients undergoing primary debulking surgery.
authors.affiliation: Department of Gynecology and Gynecologic Oncology, Kliniken Essen-Mitte, Evangelische Huyssens-Stiftung, Henricistrasse 92, 45136 Essen, Germany. Electronic address: b.ataseven@kliniken-essen-mitte.de.
authors.forename: Beyhan
authors.initials: B
authors.lastname: Ataseven
authors.affiliation: Department of Gynecology and Gynecologic Oncology, Kliniken Essen-Mitte, Evangelische Huyssens-Stiftung, Henricistrasse 92, 45136 Essen, Germany.
authors.forename: Christoph
authors.initials: C
authors.lastname: Grimm
authors.affiliation: Department of Gynecology and Gynecologic Oncology, Kliniken Essen-Mitte, Evangelische Huyssens-Stiftung, Henricistrasse 92, 45136 Essen, Germany.
authors.forename: Philipp
authors.initials: P
authors.lastname: Harter
authors.affiliation: Department of Gynecology and Gynecologic Oncology, Kliniken Essen-Mitte, Evangelische Huyssens-Stiftung, Henricistrasse 92, 45136 Essen, Germany.
authors.forename: Sonia
authors.initials: S
authors.lastname: Prader
authors.affiliation: Department of Gynecology and Gynecologic Oncology, Kliniken Essen-Mitte, Evangelische Huyssens-Stiftung, Henricistrasse 92, 45136 Essen, Germany.
authors.forename: Alexander
authors.initials: A
authors.lastname: Traut
authors.affiliation: Department of Gynecology and Gynecologic Oncology, Kliniken Essen-Mitte, Evangelische Huyssens-Stiftung, Henricistrasse 92, 45136 Essen, Germany.
authors.forename: Florian
authors.initials: F
authors.lastname: Heitz
authors.affiliation: Department of Gynecology and Gynecologic Oncology, Kliniken Essen-Mitte, Evangelische Huyssens-Stiftung, Henricistrasse 92, 45136 Essen, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: du Bois
mesh_terms: D000077216:Carcinoma, Ovarian Epithelial; D005260:Female; D006801:Humans; D008197:Lymph Node Excision; D008198:Lymph Nodes / Q000473:pathology* / Q000601:surgery; D008207:Lymphatic Metastasis; D008875:Middle Aged; D009367:Neoplasm Staging; D009375:Neoplasms, Glandular and Epithelial / Q000473:pathology* / Q000601:surgery; D010051:Ovarian Neoplasms / Q000473:pathology* / Q000601:surgery; D011379:Prognosis; D012189:Retrospective Studies
keywords: Lymph node ratio; Ovarian cancer; Prognosis; Systematic lymphadenectomy