title: The importance of blood loss during colon cancer surgery for long-term survival: an epidemiological study based on a population based register.
abstract: OBJECTIVE
  This study tested the hypothesis that the amount of blood loss during surgery for colonic cancer influences long-term survival.
  
  
  BACKGROUND
  The perioperative blood loss during surgery for colorectal cancer relates to the risk for complications and early mortality.
  
  
  METHODS
  All patients who underwent surgery for colon cancer between 1997 and 2003 in the health-care region of Uppsala/Örebro were prospectively registered at the regional oncological center. Data on patients who underwent radical surgery for stages I to III disease were analyzed. Patients who died within 6 months after surgery were excluded. Hazard ratios were calculated with uni- and multivariate Cox proportional hazard regression. Because of covariation, blood loss, blood transfusion, and complications were tested in separate multivariate analyses.
  
  
  RESULTS
  Blood loss of 250 mL or more during surgery, male gender, occurrence of complications, age more than 75 years, and stage III disease were risk factors for overall mortality in the uni- and multivariate analyses. Perioperative blood transfusion was shown to be a risk factor in the univariate analysis only.
  
  
  CONCLUSIONS
  The results support the hypothesis that degree of blood loss during surgery for colon cancer is a factor that influences long-term survival.
authors.affiliation: Division of Surgery, Department for Clinical Science, Intervention and Technology, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden. malin.morner@ki.se
authors.forename: Malin E M
authors.initials: ME
authors.lastname: Mörner
authors.forename: Ulf
authors.initials: U
authors.lastname: Gunnarsson
authors.forename: Pia
authors.initials: P
authors.lastname: Jestin
authors.forename: Monika
authors.initials: M
authors.lastname: Svanfeldt
mesh_terms: D000368:Aged; D016063:Blood Loss, Surgical; D003082:Colectomy / Q000009:adverse effects / Q000401:mortality*; D003110:Colonic Neoplasms / Q000401:mortality* / Q000601:surgery; D005260:Female; D006801:Humans; D008297:Male; D012042:Registries; D012307:Risk Factors; D016019:Survival Analysis; D013997:Time Factors; D016896:Treatment Outcome