title: Primary tumour resection and survival in the palliative management of metastatic colorectal cancer.
abstract: OBJECTIVE
  To examine whether surgical resection of the primary tumour confers a survival benefit and to identify the predictive factors of outcome in patients presenting with asymptomatic metastatic colorectal cancer (CRC).
  
  
  METHODS
  A review of a hospital database in a tertiary institution over a 6-year period (1999-2005) revealed 70 patients with asymptomatic primary CRC and unresectable liver metastases treated initially by systemic chemotherapy. A multivariate regression analysis model was used to determine the relative influence of multiple tumours, single/multiple liver metastases, tumour site, differentiation, response of liver and primary tumour to chemotherapy, biochemical response to chemotherapy, age at presentation, performance status and surgical intervention for the CRC primary.
  
  
  RESULTS
  In 67 cases (3 lost to follow-up), 63 had multiple and 4 single surgically irresectable liver metastases. A total of 41 deaths were recorded. All patients received systemic chemotherapy and surgery was performed for bowel obstruction, bleeding or stable disease (n=32). Surgery (OR 0.26; p=0.00013) and clinical response of the primary tumour (OR 0.53; p=0.012) were independently associated with prolonged survival. Proximal tumours (OR 2.61; p=0.0075) and multiple primaries (OR 3.37; p=0.02) were associated with poor outcome.
  
  
  CONCLUSIONS
  Surgical resection and response of the primary tumour to chemotherapy may be associated with improved survival, but proximal or multiple cancers predict poor outcome in patients with asymptomatic CRC and unresectable metastatic disease.
authors.affiliation: Department of Surgery, University College London Hospitals, London, UK.
authors.forename: A
authors.initials: A
authors.lastname: Bajwa
authors.forename: N
authors.initials: N
authors.lastname: Blunt
authors.forename: S
authors.initials: S
authors.lastname: Vyas
authors.forename: I
authors.initials: I
authors.lastname: Suliman
authors.forename: J
authors.initials: J
authors.lastname: Bridgewater
authors.forename: D
authors.initials: D
authors.lastname: Hochhauser
authors.forename: J A
authors.initials: JA
authors.lastname: Ledermann
authors.forename: A
authors.initials: A
authors.lastname: O'Bichere
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D015179:Colorectal Neoplasms / Q000401:mortality* / Q000473:pathology / Q000601:surgery*; D013505:Digestive System Surgical Procedures / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008113:Liver Neoplasms / Q000401:mortality / Q000556:secondary* / Q000628:therapy; D008297:Male; D008875:Middle Aged; D009362:Neoplasm Metastasis; D009367:Neoplasm Staging; D010166:Palliative Care / Q000379:methods*; D011379:Prognosis; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D015996:Survival Rate / Q000639:trends; D006113:United Kingdom / Q000453:epidemiology