title: Resection margin influences the outcome of patients with bilobar colorectal liver metastases.
abstract: OBJECTIVE
  To evaluate the outcome of patients with bilobar colorectal liver metastases (CRLM) and identify clinico-pathological variables that influenced survival.
  
  
  METHODS
  Patients with bilobar CRLM were identified from a prospectively maintained hepatobiliary database during the study period (January 2010-June 2014). Collated data included demographics, primary tumour treatment, surgical data, histopathology analysis and clinical outcome. Down-staging therapy included Oxaliplatin- or Irinotecan- based regimens, and Cetuximab was also used in patients that wereK-RASwild-type. Response to neo-adjuvant therapy was assessed at the multi-disciplinary team meeting and considered for surgery if all macroscopic CRLM were resectable with a clear margin while preserving sufficient liver parenchyma.
  
  
  RESULTS
  Of the 136 patients included, thirty-two (23.5%) patients were considered inoperable and referred for palliative chemotherapy, and thirty-four (25%) patients underwent liver resection. Seventy (51.4%) patients underwent down-staging therapy, of which 37 (52.8%) patients responded sufficiently to undergo liver resection. Patients that failed to respond to down-staging therapy (n= 33, 47.1%) were referred for palliative therapy. There was a significant difference in overall survival between the three groups (surgeryvsdown-staging therapyvsinoperable disease,P< 0.001). All patients that underwent hepatic resection, including patients that had down-staging therapy, had a significantly better overall survival compared to patients that were inoperable (P< 0.001). On univariate analysis, only resection margin significantly influenced disease-free survival (P= 0.017). On multi-variate analysis, R0 resection (P= 0.030) and female (P= 0.036) gender significantly influenced overall survival.
  
  
  CONCLUSIONS
  Patients undergoing liver resection with bilobar CRLM have a significantly better survival outcome. R0 resection is associated with improved disease-free and overall survival in this patient group.
authors.affiliation: Sara Di Carlo, Department of General Surgery, University of Rome, 00185 Tor Vergata, Italy.
authors.forename: Sara
authors.initials: S
authors.lastname: Di Carlo
authors.affiliation: Sara Di Carlo, Department of General Surgery, University of Rome, 00185 Tor Vergata, Italy.
authors.forename: Derek
authors.initials: D
authors.lastname: Yeung
authors.affiliation: Sara Di Carlo, Department of General Surgery, University of Rome, 00185 Tor Vergata, Italy.
authors.forename: Jamie
authors.initials: J
authors.lastname: Mills
authors.affiliation: Sara Di Carlo, Department of General Surgery, University of Rome, 00185 Tor Vergata, Italy.
authors.forename: Abed
authors.initials: A
authors.lastname: Zaitoun
authors.affiliation: Sara Di Carlo, Department of General Surgery, University of Rome, 00185 Tor Vergata, Italy.
authors.forename: Iain
authors.initials: I
authors.lastname: Cameron
authors.affiliation: Sara Di Carlo, Department of General Surgery, University of Rome, 00185 Tor Vergata, Italy.
authors.forename: Dhanny
authors.initials: D
authors.lastname: Gomez
keywords: Chemotherapy; Colorectal liver metastases; Liver resection