title: Incorporating Neutrophil-to-lymphocyte Ratio and Platelet-to-lymphocyte Ratio in Place of Neutrophil Count and Platelet Count Improves Prognostic Accuracy of the International Metastatic Renal Cell Carcinoma Database Consortium Model.
abstract: OBJECTIVE
  The study investigated whether a replacement of neutrophil count and platelet count by neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) within the International Metastatic Renal Cell Carcinoma Database Consortium (IMDC) model would improve its prognostic accuracy.
  
  
  METHODS
  This retrospective analysis included consecutive patients with metastatic renal cell carcinoma treated with first-line tyrosine kinase inhibitors. The IMDC and modified-IMDC models were compared using: concordance index (CI), bias-corrected concordance index (BCCI), calibration plots, the Grønnesby and Borgan test, Bayesian Information Criterion (BIC), generalized R2, Integrated Discrimination Improvement (IDI), and continuous Net Reclassification Index (cNRI) for individual risk factors and the three risk groups.
  
  
  RESULTS
  Three hundred and twenty-one patients were eligible for analyses. The modified-IMDC model with NLR value of 3.6 and PLR value of 157 was selected for comparison with the IMDC model. Both models were well calibrated. All other measures favoured the modified-IMDC model over the IMDC model (CI, 0.706 vs. 0.677; BCCI, 0.699 vs. 0.671; BIC, 2,176.2 vs. 2,190.7; generalized R2, 0.238 vs. 0.202; IDI, 0.044; cNRI, 0.279 for individual risk factors; and CI, 0.669 vs. 0.641; BCCI, 0.669 vs. 0.641; BIC, 2,183.2 vs. 2,198.1; generalized R2, 0.163 vs. 0.123; IDI, 0.045; cNRI, 0.165 for the three risk groups).
  
  
  CONCLUSIONS
  Incorporation of NLR and PLR in place of neutrophil count and platelet count improved prognostic accuracy of the IMDC model. These findings require external validation before introducing into clinical practice.
authors.affiliation: Department of Oncology, Military Institute of Medicine, Warsaw, Poland.
authors.forename: Pawel
authors.initials: P
authors.lastname: Chrom
authors.affiliation: Department of Oncology, Military Institute of Medicine, Warsaw, Poland.
authors.forename: Rafal
authors.initials: R
authors.lastname: Stec
authors.affiliation: Department of Oncology, Military Institute of Medicine, Warsaw, Poland.
authors.forename: Lubomir
authors.initials: L
authors.lastname: Bodnar
authors.affiliation: Department of Oncology, Military Institute of Medicine, Warsaw, Poland.
authors.forename: Cezary
authors.initials: C
authors.lastname: Szczylik
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001792:Blood Platelets / Q000276:immunology / Q000473:pathology*; D002292:Carcinoma, Renal Cell / Q000097:blood* / Q000401:mortality / Q000473:pathology; D016208:Databases, Factual; D005260:Female; D006801:Humans; D007962:Leukocytes / Q000276:immunology / Q000473:pathology*; D018655:Lymphocyte Count; D008297:Male; D008875:Middle Aged; D009362:Neoplasm Metastasis; D009504:Neutrophils / Q000276:immunology / Q000473:pathology*; D010976:Platelet Count; D011379:Prognosis; D012189:Retrospective Studies; D012307:Risk Factors; D016019:Survival Analysis; D055815:Young Adult
keywords: International Metastatic Renal Cell Carcinoma Database Consortium model; Neutrophil-to-lymphocyte ratio; Overall survival; Platelet-to-lymphocyte ratio; Prognosis; Tyrosine kinase inhibitors