title: Tumour biology of colorectal liver metastasis is a more important factor in survival than surgical margin clearance in the era of modern chemotherapy regimens.
abstract: BACKGROUND
  The aim of the authors was to reassess the impact of a positive surgical margin (R1) after a liver resection for colorectal liver metastases (CLMs) on survival in the era of modern chemotherapy, through their own experience and a literature review.
  
  
  METHODS
  Inclusion criteria were: R1 or R0 resection with no local treatment modalities, extra-hepatic metastases or other cancer.
  
  
  RESULTS
  Among 337 patients operated between 2000 and 2010, 273 patients were eligible (214 R0/59 R1). The mean follow-up was 43 ± 29 months. Compared with a R0 resection, a R1 resection offered a lower 5-year overall (39.1% versus 54.2%, P = 0.010), disease-free (15.2% versus 31.1%, P = 0.021) and progression-free (i.e. time to the first non-curable recurrence; 33.1% versus 47.3%, P = 0.033) survival rates. Metastases in the R1 group were more numerous, larger and more frequently synchronous. Independent factors of poor survival were: number, size and short-time interval of CLM occurrence, N status, rectal primary, absence of adjuvant chemotherapy, but not a R1 resection. With the more-systematic administration of chemotherapy since 2005, the intergroup difference in progression-free survival disappeared (P = 0.264).
  
  
  CONCLUSIONS
  A R1 resection had no prognostic value per se but reflected a more severe disease. The recent change in the prognostic value of a R1 resection may be linked to the beneficial effect of chemotherapy.
authors.affiliation: Department of Digestive Surgery and Transplantation, Lille University Medical Center, University of Lille Nord de France, Lille, France.
authors.forename: Stéphanie
authors.initials: S
authors.lastname: Truant
authors.forename: Cédric
authors.initials: C
authors.lastname: Séquier
authors.forename: Emmanuelle
authors.initials: E
authors.lastname: Leteurtre
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Boleslawski
authors.forename: Mehdi
authors.initials: M
authors.lastname: Elamrani
authors.forename: Guillemette
authors.initials: G
authors.lastname: Huet
authors.forename: Alain
authors.initials: A
authors.lastname: Duhamel
authors.forename: Mohamed
authors.initials: M
authors.lastname: Hebbar
authors.forename: François-René
authors.initials: FR
authors.lastname: Pruvot
mesh_terms: D000368:Aged; D000970:Antineoplastic Agents / Q000627:therapeutic use; D017024:Chemotherapy, Adjuvant; D003110:Colonic Neoplasms / Q000473:pathology; D006498:Hepatectomy; D006801:Humans; D008113:Liver Neoplasms / Q000401:mortality* / Q000473:pathology* / Q000556:secondary / Q000628:therapy; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009364:Neoplasm Recurrence, Local / Q000453:epidemiology; D011379:Prognosis; D057216:Propensity Score; D012004:Rectal Neoplasms / Q000473:pathology; D016019:Survival Analysis
chemical_list: D000970:Antineoplastic Agents