title: Prognostic Significance of Tissue Leptin Expression in Colorectal Cancer Patients.
abstract: OBJECTIVE
  Leptin is encoded by the ob gene and is involved in the control of food intake and energy expenditure. Recent studies have implicated leptin expression to be an indicator of tumor features and prognosis. The purpose of this study was to investigate the association of tissue expression of leptin with the clinicopathological characteristics and clinical outcomes in colorectal cancer patients.
  
  
  METHODS
  Patients who had undergone a curative surgical resection for a colorectal adenocarcinoma from 2000 to 2004 were included in the study. Immunohistochemical analyses of leptin expression were performed, and clinicopathological parameters were evaluated.
  
  
  RESULTS
  Clinical data and tumor tissues of 146 patients were evaluated. The mean age was 68.6 ± 11.3 years, and 61.0% were men. Immunohistochemically, the rates of negative, weak, moderate, and strong leptin expression were 2.7% (4 of 146), 5.5% (8 of 146), 43.2% (63 of 146), and 48.6% (71 of 146), respectively. We compared the negative, weak, and moderate expression group (group A) with the strong expression group (group B). Leptin expression was inversely associated with nodal stage (P = 0.007) between the two groups. Leptin expression was not significantly associated with differentiation (P = 0.37), T stage (P = 0.16), and American Joint Committee on Cancer stage (P = 0.49), and no significant differences in the disease-free and the overall survivals (P = 0.78 and P = 0.61) were observed.
  
  
  CONCLUSIONS
  Results demonstrated an inverse association of nodal stage with high leptin expression. Higher leptin expression level might predict better oncologic outcome. However, further studies are warranted to identify the exact role of leptin expression in colorectal cancer.
authors.affiliation: Department of Surgery, Keimyung University Dongsan Medical Center, Keimyung University School of Medicine, Daegu, Korea.
authors.forename: Woon Kyung
authors.initials: WK
authors.lastname: Jeong
authors.affiliation: Department of Surgery, Keimyung University Dongsan Medical Center, Keimyung University School of Medicine, Daegu, Korea.
authors.forename: Seong Kyu
authors.initials: SK
authors.lastname: Baek
authors.affiliation: Department of Internal Medicine, Keimyung University Dongsan Medical Center, Keimyung University School of Medicine, Daegu, Korea.
authors.forename: Mi Kyung
authors.initials: MK
authors.lastname: Kim
authors.affiliation: Department of Pathology, Keimyung University Dongsan Medical Center, Keimyung University School of Medicine, Daegu, Korea.
authors.forename: Sun Young
authors.initials: SY
authors.lastname: Kwon
authors.affiliation: Department of Internal Medicine, Keimyung University Dongsan Medical Center, Keimyung University School of Medicine, Daegu, Korea.
authors.forename: Hye Soon
authors.initials: HS
authors.lastname: Kim
keywords: Colorectal neoplasms; Immunohistochemistry; Leptin; Survival rate; Tissue array analysis
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