title: Trends in port-site metastasis after laparoscopic resection of incidental gallbladder cancer: A systematic review.
abstract: The risk of port-site metastasis after laparoscopic removal of incidental gallbladder cancer was previously estimated to be 14-30%. The present study was designed to determine the incidence of port-site metastasis in incidental gallbladder cancer in the modern era (2000-2014) versus the historic era (1991-1999). We also investigated the site of port-site metastasis.
  
  
  
  Using PRISMA, a systematic review was conducted to identify papers that addressed the development of port-site metastasis after laparoscopic resection of incidental gallbladder cancer. Studies that described cancer-specific outcomes in ≥5 patients were included. A validated quality appraisal tool was used, and a weighted estimate of the incidence of port-site metastasis was calculated.
  
  
  
  Based on data extracted from 27 papers that met inclusion criteria, the incidence of port-site metastasis in incidental gallbladder cancer has decreased from 18.6% prior to 2000 (95% confidence interval 15.3-21.9%, n = 7) to 10.3% since then (95% confidence interval 7.9-12.7%, n = 20) (P < .001). The extraction site is at significantly higher risk than nonextraction sites.
  
  
  
  The incidence of port-site metastasis in incidental gallbladder cancer has decreased but remains high relative to other primary tumors. Any preoperative finding that raises the suspicion of gallbladder cancer should prompt further investigation and referral to a hepato-pancreato-biliary specialist.
authors.affiliation: Division of General Surgery, Department of Surgery, University of Toronto, Toronto, Ontario, Canada; Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada; Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada.
authors.forename: David
authors.initials: D
authors.lastname: Berger-Richardson
authors.affiliation: Division of General Surgery, Department of Surgery, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Tyler R
authors.initials: TR
authors.lastname: Chesney
authors.affiliation: Library and Information Services, University Health Network, Toronto, Ontario, Canada.
authors.forename: Marina
authors.initials: M
authors.lastname: Englesakis
authors.affiliation: Division of General Surgery, Department of Surgery, University of Toronto, Toronto, Ontario, Canada; Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada; Institute of Health Policy, Management, and Evaluation, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Anand
authors.initials: A
authors.lastname: Govindarajan
authors.affiliation: Division of General Surgery, Department of Surgery, University of Toronto, Toronto, Ontario, Canada; Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada; Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada.
authors.forename: Sean P
authors.initials: SP
authors.lastname: Cleary
authors.affiliation: Division of General Surgery, Department of Surgery, University of Toronto, Toronto, Ontario, Canada; Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada; Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada. Electronic address: cswallow@mtsinai.on.ca.
authors.forename: Carol J
authors.initials: CJ
authors.lastname: Swallow
mesh_terms: D017081:Cholecystectomy, Laparoscopic / Q000009:adverse effects*; D005706:Gallbladder Neoplasms / Q000453:epidemiology / Q000473:pathology* / Q000601:surgery*; D006801:Humans; D015994:Incidence; D033162:Incidental Findings; D009366:Neoplasm Seeding; D013997:Time Factors