title: Prognostic discrimination of subgrouping node-positive endometrioid uterine cancer: location vs nodal extent.
abstract: BACKGROUND
  The 2009 International Federation of Gynecologists and Obstetricians elected to substage patients with positive retroperitoneal lymph nodes as IIIC 1 (pelvic lymph node metastasis only) and IIIC 2 (paraaortic node metastasis with or with positive pelvic lymph nodes). We have investigated the discriminatory ability of subgrouping patients with retroperitoneal nodal involvement based on location, number, and ratio of positive nodes.
  
  
  METHODS
  For 1075 patients with stage IIIC endometrioid corpus cancer abstracted from the Surveillance, Epidemiology, and End Results databases for 2003-2007, Kaplan-Meier analyses, Cox proportional hazard models, and other quantitative measures were used to compare the prognostic discrimination for disease-specific survival (DSS) of nodal subgroupings.
  
  
  RESULTS
  In univariate analysis, the 3-year DSS were significantly different for subgroupings by location (IIIC 1 vs IIIC 2; 80.5% vs 67.0%, respectively, P=0.001), lymph node ratio (≤ 23.2% vs >23.2%; 80.8% vs 67.6%; P<0.001), and number of positive lymph nodes (1, 2-5, >5; 79.5, 75.4, 62.9%, P=0.016). The ratio of positive nodes showed superior discriminatory substaging in Cox models.
  
  
  CONCLUSIONS
  Subgrouping of stage IIIC patients by the ratio of positive nodes, either as a dichotomized or continuous parameter, shows the strongest ability to discriminate the survival, controlling for other confounding factors.
authors.affiliation: Department of Radiation Oncology, Stanford University School of Medicine, Cancer Center, 875 Blake Wilbur Drive, Stanford, CA 94305, USA. dskapp@stanford.edu
authors.forename: D S
authors.initials: DS
authors.lastname: Kapp
authors.forename: T K
authors.initials: TK
authors.lastname: Kiet
authors.forename: J K
authors.initials: JK
authors.lastname: Chan
mesh_terms: D005260:Female; D006801:Humans; D008207:Lymphatic Metastasis / Q000473:pathology*; D008875:Middle Aged; D011379:Prognosis; D016016:Proportional Hazards Models; D016019:Survival Analysis; D014594:Uterine Neoplasms / Q000473:pathology*