title: Regional lymph node involvement in patients undergoing liver resection for colorectal cancer metastases.
abstract: BACKGROUND
  While the indications for surgery among patients with colorectal cancer liver metastases (CRCLM) are expanding, the role of surgery in patients with hepatic lymph node involvement remains controversial. We report management and outcomes in a population-based cohort of patients undergoing hepatectomy with concomitant hepatic lymphadenectomy for CRCLM.
  
  
  METHODS
  All cases of hepatectomy for CRCLM in the Canadian Province of Ontario from 2002 to 2009 were identified using the population-based Ontario Cancer Registry and linked electronic records of treatment. Pathology reports were used to identify concomitant lymphadenectomy with liver resection as well as extent of disease and surgical procedure.
  
  
  RESULTS
  Among 1310 patients who underwent resection for CRCLM, 103 (8%) underwent simultaneous regional lymphadenectomy. Seventy-one percent of cases with lymphadenectomy (70/103) had a major liver resection (≥3 segments). Of the 103 lymphadenectomy cases, 80 (78%) were hepatic pedicle, 16 (16%) were celiac and 7 (7%) were para-aortic. The mean number of nodes removed was 2.2 (range 1-15). Ninety-day mortality was 6%. Twenty-nine percent (30/103) of cases had positive nodes. Unadjusted overall survival at 5 years for positive vs negative nodes was 21% vs 42% (p = 0.003); cancer-specific survival was 10% vs 43% (p < 0.001). In adjusted analyses, hepatic node involvement was associated with inferior OS (HR 2.19, p = 0.010) and CSS (HR 3.07, p = 0.002).
  
  
  CONCLUSIONS
  Patients with resected CRC liver metastases with regional lymph node involvement have inferior survival compared to patients with negative nodes. Despite this poor prognostic factor, a small proportion of cases with involved nodes will achieve long-term survival.
authors.affiliation: Department of Surgery, Queen's University, Kingston, Ontario, Canada; Department of Oncology, Queen's University, Kingston, Ontario, Canada. Electronic address: nanjis@kgh.kari.net.
authors.forename: S
authors.initials: S
authors.lastname: Nanji
authors.affiliation: Department of Surgery, St. Joseph's Hospital, Toronto, Ontario, Canada.
authors.forename: M E
authors.initials: ME
authors.lastname: Tsang
authors.affiliation: Department of Public Health Sciences, Queen's University, Kingston, Ontario, Canada.
authors.forename: X
authors.initials: X
authors.lastname: Wei
authors.affiliation: Department of Oncology, Queen's University, Kingston, Ontario, Canada; Department of Public Health Sciences, Queen's University, Kingston, Ontario, Canada.
authors.forename: C M
authors.initials: CM
authors.lastname: Booth
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015179:Colorectal Neoplasms / Q000453:epidemiology / Q000473:pathology*; D005260:Female; D006498:Hepatectomy; D006801:Humans; D008113:Liver Neoplasms / Q000556:secondary* / Q000601:surgery*; D008197:Lymph Node Excision; D008207:Lymphatic Metastasis / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D009864:Ontario / Q000453:epidemiology; D012042:Registries; D012189:Retrospective Studies; D015996:Survival Rate; D016896:Treatment Outcome
keywords: Colorectal cancer liver metastases; Liver resection; Lymphadenectomy; Population-based study