title: Low preoperative lymphocyte-monocyte ratio (LMR) represents a potentially poor prognostic factor in nonmetastatic clear cell renal cell carcinoma.
abstract: OBJECTIVE
  To explore the potential prognostic significance of the lymphocyte-monocyte ratio (LMR) in patients with nonmetastatic renal cell carcinoma (RCC), as the LMR has been repeatedly proposed to have a negative effect on patient׳s survival in various hematological and solid cancers. However, findings about LMR׳s prognostic significance in RCC have not been reported yet.
  
  
  METHODS
  We retrospectively evaluated the prognostic significance of the LMR in a cohort comprising 678 patients with nonmetastatic clear cell RCC, who were operated between 2000 and 2010 with curative radical or partial nephrectomy at a single tertiary academic center. Preoperative LMR was calculated 1 day before surgical intervention. Patients were categorized using an LMR cutoff of 3.0. Cancer-specific survival (CSS), metastasis-free survival, and overall survival were assessed using the Kaplan-Meier method. To evaluate the independent prognostic significance of the LMR, multivariate Cox regression models were applied. Additionally, the influence of the LMR on the predictive accuracy of the Leibovich prognosis score was determined using the Harrell concordance index (c-index) and decision curve analysis.
  
  
  RESULTS
  Low LMR was statistically significantly associated with older patients (≥65 y), high tumor grade (G3+G4), advanced pathologic T category (pT3+pT4), the presence of histologic tumor necrosis, and male gender (P<0.05). Multivariate analysis identified a low LMR as an independent prognostic factor for patients׳ CSS (hazard ratio = 2.33; 95% CI: 1.10-4.94; P = 0.027). The estimated c-index was 0.83 using the Leibovich prognosis score and 0.86 when the LMR was added.
  
  
  CONCLUSIONS
  Regarding CSS of patients with RCC, a decreased LMR represents an independent prognostic factor. Adding the LMR to well-established prognostic models, such as the Leibovich prognosis score, might improve their predictive ability.
authors.affiliation: Department of Urology, Medical University of Graz, Graz, Austria. Electronic address: g.hutterer@gmail.com.
authors.forename: Georg C
authors.initials: GC
authors.lastname: Hutterer
authors.affiliation: Division of Oncology, Department of Internal Medicine, Medical University of Graz, Graz, Austria.
authors.forename: Caroline
authors.initials: C
authors.lastname: Stoeckigt
authors.affiliation: Clinical Institute of Medical and Chemical Laboratory Diagnostics, Medical University of Graz, Graz, Austria.
authors.forename: Tatjana
authors.initials: T
authors.lastname: Stojakovic
authors.affiliation: Department of Urology, Medical University of Graz, Graz, Austria.
authors.forename: Johanna
authors.initials: J
authors.lastname: Jesche
authors.affiliation: Research Facility for Biostatistics, Medical University of Graz, Graz, Austria.
authors.forename: Katharina
authors.initials: K
authors.lastname: Eberhard
authors.affiliation: Department of Urology, Medical University of Graz, Graz, Austria.
authors.forename: Karl
authors.initials: K
authors.lastname: Pummer
authors.affiliation: Department of Urology, Medical University of Graz, Graz, Austria.
authors.forename: Richard
authors.initials: R
authors.lastname: Zigeuner
authors.affiliation: Division of Oncology, Department of Internal Medicine, Medical University of Graz, Graz, Austria; Department of Experimental Therapeutics, The University of Texas MD Anderson Cancer Center, Houston, TX.
authors.forename: Martin
authors.initials: M
authors.lastname: Pichler
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002292:Carcinoma, Renal Cell / Q000276:immunology* / Q000401:mortality / Q000473:pathology*; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D007680:Kidney Neoplasms / Q000276:immunology* / Q000401:mortality / Q000473:pathology*; D018655:Lymphocyte Count; D008214:Lymphocytes; D008297:Male; D008875:Middle Aged; D009000:Monocytes; D011379:Prognosis; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D055815:Young Adult
keywords: Prognosis; Renal cell carcinoma; Validation study