title: A critical appraisal of circumferential resection margins in esophageal carcinoma.
abstract: BACKGROUND
  In esophageal cancer, circumferential resection margins (CRMs) are considered to be of relevant prognostic value, but a reliable definition of tumor-free CRM is still unclear. The aim of this study was to appraise the clinical prognostic value of microscopic CRM involvement and to determine the optimal limit of CRM.
  
  
  METHODS
  To define the optimal tumor-free CRM we included 98 consecutive patients who underwent extended esophagectomy with microscopic tumor-free resection margins (R0) between 1997 and 2006. CRMs were measured in tenths of millimeters with inked lateral margins. Outcome of patients with CRM involvement was compared with a statistically comparable control group of 21 patients with microscopic positive resection margins (R1).
  
  
  RESULTS
  A cutoff point of CRM at < or = 1.0 mm and > 1.0 mm appeared to be an adequate marker for survival and prognosis (both P < 0.001). The outcome in patients with CRMs < or = 1.0 and > 0 mm was equal to that in patients with CRM of 0 mm (P = 0.43). CRM involvement was an independent prognostic factor for both recurrent disease (P = 0.001) and survival (P < 0.001). Survival of patients with positive CRMs (< or = 1 mm) did not significantly differ from patients with an R1 resection (P = 0.12).
  
  
  CONCLUSIONS
  Involvement of the circumferential resection margins is an independent prognostic factor for recurrent disease and survival in esophageal cancer. The optimal limit for a positive CRM is < or = 1 mm and for a free CRM is >1.0 mm. Patients with unfavorable CRM should be approached as patients with R1 resection with corresponding outcome.
authors.affiliation: Department of Surgery, Division of Surgical Oncology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands.
authors.forename: Bareld B
authors.initials: BB
authors.lastname: Pultrum
authors.forename: Judith
authors.initials: J
authors.lastname: Honing
authors.forename: Justin K
authors.initials: JK
authors.lastname: Smit
authors.forename: Hendrik M
authors.initials: HM
authors.lastname: van Dullemen
authors.forename: Gooitzen M
authors.initials: GM
authors.lastname: van Dam
authors.forename: Henk
authors.initials: H
authors.lastname: Groen
authors.forename: Harry
authors.initials: H
authors.lastname: Hollema
authors.forename: John Th M
authors.initials: JT
authors.lastname: Plukker
mesh_terms: D000230:Adenocarcinoma / Q000473:pathology / Q000601:surgery*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002294:Carcinoma, Squamous Cell / Q000473:pathology / Q000601:surgery*; D004938:Esophageal Neoplasms / Q000473:pathology / Q000601:surgery*; D016629:Esophagectomy; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000473:pathology / Q000601:surgery*; D009367:Neoplasm Staging; D011379:Prognosis; D015996:Survival Rate