title: Impact of a lymphocyte to monocyte ratio in stage IV colorectal cancer.
abstract: BACKGROUND
  Recent studies have proposed that the use of the lymphocyte-to-monocyte ratio (LMR) is a good prognostic indicator for patients with nonmetastatic colorectal cancer (CRC). In the present study, we aimed to evaluate the prognostic impact of the LMR in stage IV CRC patients who have undergone curative resection.
  
  
  METHODS
  We performed a retrospective review of 117 stage IV CRC patients who underwent curative resection at our institute between 1997 and 2012. Patients were divided into a low-LMR group and a high-LMR group according to their LMR. The cutoff value of the LMR was determined based on receiver operating characteristics curve analysis. The relationships between the LMR and disease-free survival (DFS) and cancer-specific survival (CSS) rates were assessed.
  
  
  RESULTS
  The cutoff value for LMR was 3.00. DFS was not significantly different between the high- and low-LMR groups (P = 0.277). By contrast, CSS was significantly better in the high-LMR group than in the low-LMR group (P = 0.001). Multivariate analysis indicated that the LMR was an independent prognostic factor for CSS in patients with stage IV CRC who had undergone curative resection (hazard ratio: 2.75; 95% confidence interval: 1.40-5.44; P = 0.004), but not for DFS.
  
  
  CONCLUSIONS
  The preoperative LMR is a simple and useful prognostic indicator in patients with stage IV CRC who have undergone curative resection.
authors.affiliation: Department of Surgical Oncology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan. Electronic address: tsu443@hotmail.com.
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Ozawa
authors.affiliation: Department of Surgical Oncology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.
authors.forename: Soichiro
authors.initials: S
authors.lastname: Ishihara
authors.affiliation: Department of Surgical Oncology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.
authors.forename: Kazushige
authors.initials: K
authors.lastname: Kawai
authors.affiliation: Department of Surgical Oncology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.
authors.forename: Shinsuke
authors.initials: S
authors.lastname: Kazama
authors.affiliation: Department of Surgical Oncology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.
authors.forename: Hironori
authors.initials: H
authors.lastname: Yamaguchi
authors.affiliation: Department of Surgical Oncology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.
authors.forename: Eiji
authors.initials: E
authors.lastname: Sunami
authors.affiliation: Department of Surgical Oncology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.
authors.forename: Joji
authors.initials: J
authors.lastname: Kitayama
authors.affiliation: Department of Surgical Oncology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Watanabe
mesh_terms: D000230:Adenocarcinoma / Q000276:immunology* / Q000401:mortality / Q000473:pathology; D000368:Aged; D003106:Colon / Q000473:pathology; D015179:Colorectal Neoplasms / Q000276:immunology* / Q000401:mortality / Q000473:pathology; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D018655:Lymphocyte Count; D008297:Male; D008875:Middle Aged; D009000:Monocytes; D016016:Proportional Hazards Models; D012007:Rectum / Q000473:pathology; D012189:Retrospective Studies; D014041:Tokyo / Q000453:epidemiology
keywords: Colorectal cancer; Lymphocyte-to-monocyte ratio; Prognosis; Stage IV