title: Prognostic significance of elevated endothelin-1 levels in patients with colorectal cancer.
abstract: BACKGROUND
  Prognostic factors from clinical, laboratory and pathological data of patients with colorectal cancer are essential to identify high-risk groups to whom beneficial adjuvant therapy could be given. Endothelin-1, a growth factor, has been associated with the development and spread of solid tumours. This prospective study was performed to determine whether preoperative plasma big ET-1 levels might be useful as a prognostic indicator in patients with colorectal carcinoma.
  
  
  METHODS
  Sixty-five consecutive patients with colorectal cancer confirmed by biopsy were included prospectively into this study over a 12-month period. Plasma samples from a peripheral vein were obtained prior to surgery. Univariate analysis of survival using age (< or > 70 years), sex, Dukes' stage (A&B versus C), tumour size (< or > 50 mm), vascular invasion and plasma big ET-1 levels was performed and significant factors were then analysed with the Cox regression model.
  
  
  RESULTS
  Three variables, age, Dukes' tumour stage and plasma big ET-1 levels, were found to have prognostic significance (p<0.05). Factors associated with a poorer prognosis were age >70 years (p=0.02), Dukes' C tumours (p=0.04) and plasma big ET-1 levels >4.2 pg/mL (p=0.02). The Cox regression model identified the same three variables as having independent prognostic value for overall survival.
  
  
  CONCLUSIONS
  Preoperative plasma big ET-1 levels may be useful in predicting overall survival in patients with colorectal cancer. Plasma big ET-1 levels may be useful in the selection of high-risk lymph node-negative patients with colorectal cancer for adjuvant therapy.
authors.affiliation: University Department of Surgery, Leicester Royal Infirmary, Leicester, United Kingdom.
authors.forename: C
authors.initials: C
authors.lastname: Arun
authors.forename: N J M
authors.initials: NJ
authors.lastname: London
authors.forename: D M
authors.initials: DM
authors.lastname: Hemingway
mesh_terms: D000368:Aged; D014408:Biomarkers, Tumor / Q000097:blood*; D015179:Colorectal Neoplasms / Q000097:blood* / Q000175:diagnosis* / Q000473:pathology; D019332:Endothelin-1 / Q000097:blood*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009362:Neoplasm Metastasis; D011379:Prognosis; D016016:Proportional Hazards Models; D011446:Prospective Studies; D013997:Time Factors
chemical_list: D014408:Biomarkers, Tumor; D019332:Endothelin-1