title: Analysis of pathological risk factors for lymph node metastasis in colorectal cancer.
abstract: OBJECTIVE
  To investigate the classification of lymph node metastasis and its related factors in colorectal cancer.
  
  
  METHODS
  One thousand one hundred and twenty-seven Patients undergoing resection of colorectal carcinoma at Zhongnan Hospital of Wuhan University from January 1990 to December 2007 were retrospectively studied. The associations between lymph node metastasis and clinicopathologic variables were evaluated with logistic regression analysis.
  
  
  RESULTS
  Univariate logistic regression analysis showed that the tumor size, depth of invasion and histological differentiation were statistically significant as risk factors for lymph node metastasis. The frequency of lymph node metastasis in patients (age <40 years) was significantly higher than in older patients (age >40 years) (P<0.01). The risk of lymph node metastasis was significantly high with increasing tumor diameter (P<0.001), depth of tumor invasion (P<0.001) and lowering tumor histological differentiation (P<0.001). Multivariate logistic regression analysis revealed that the significant risk factors of lymph node metastasis included depth of tumor invasion (P<0.001) and grade of histological differentiation (P<0.001), while the former was the most important one among all clinicopathologic variables.
  
  
  CONCLUSIONS
  Depth of tumor invasion and grade of histological differentiation are independent predictive factors for lymph node metastasis. The histological differentiation was the most important risk factor among all clinicopathologic variables.
authors.affiliation: Department of Oncology, Zhongnan Hospital of Wuhan University, Hubei Cancer Clinical Study Center, Hubei Key Laboratory of Tumor Biological Behaviors; Wuhan, Hubei, PR China.
authors.forename: Wenfeng
authors.initials: W
authors.lastname: Fang
authors.forename: Biao
authors.initials: B
authors.lastname: Fan
authors.forename: Bin
authors.initials: B
authors.lastname: Xiong
mesh_terms: D000230:Adenocarcinoma / Q000556:secondary*; D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D015179:Colorectal Neoplasms / Q000473:pathology*; D005260:Female; D006801:Humans; D016015:Logistic Models; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D012189:Retrospective Studies; D012307:Risk Factors; D012737:Sex Factors; D055815:Young Adult