title: Intraoperative surgical margin re-resection for colorectal liver metastasis: is it worth the effort?
abstract: OBJECTIVE
  This study was conducted to evaluate recurrence and survival among patients who underwent intraoperative margin re-resection for colorectal cancer liver metastases (CRLM).
  
  
  BACKGROUND
  Among patients who receive intraoperative margin re-resection, the relation between final margin status, pattern of recurrence, and survival is largely unknown.
  
  
  METHODS
  Three hundred thirty-two patients who underwent hepatic resection for CRLM between 2000 and 2013 were identified. Demographics, operative data, pathologic margin status, site of recurrence, and long-term survival data were collected and analyzed. Patients were stratified in three groups based on their margin status: R0, R1, and R1 → R0.
  
  
  RESULTS
  R0 resections were achieved in 247 (74.4%) patients, 61 (18.4%) patients had an R1 resection, whereas 24 (7.2%) had an R1 → R0. Median survival for patients undergoing R0 resections was 50.2 (95% confidence interval (CI) 49.2-66.2) months versus 63.0 (95% CI 50.3-70.5) months for patients undergoing R1 resections versus 49.2 (95% CI 29.9-NA) months for patients undergoing intraoperative margin re-resection (P > 0.05). Differences in recurrence rate and pattern were not significant between the three groups (P > 0.05).
  
  
  CONCLUSIONS
  In the era of modern systemic chemotherapy, it seems that the impact of margin status on outcomes may be minimal compared to that of patient and tumor factors. In this scenario, margin re-resection to achieve R0 status does not improve long-term outcomes.
authors.affiliation: Division of Surgical Oncology, Department of Surgery, Johns Hopkins Hospital, 600 N. Wolfe Street, Blalock 688, Baltimore, MD, 21287, USA.
authors.forename: Georgios A
authors.initials: GA
authors.lastname: Margonis
authors.forename: Gaya
authors.initials: G
authors.lastname: Spolverato
authors.forename: Yuhree
authors.initials: Y
authors.lastname: Kim
authors.forename: Aslam
authors.initials: A
authors.lastname: Ejaz
authors.forename: Timothy M
authors.initials: TM
authors.lastname: Pawlik
mesh_terms: D000230:Adenocarcinoma / Q000401:mortality / Q000556:secondary* / Q000601:surgery*; D000328:Adult; D000368:Aged; D015179:Colorectal Neoplasms / Q000401:mortality / Q000473:pathology* / Q000601:surgery; D005260:Female; D006498:Hepatectomy; D006801:Humans; D008113:Liver Neoplasms / Q000401:mortality / Q000556:secondary* / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D015996:Survival Rate; D016896:Treatment Outcome