title: Extrahepatic bile duct adenocarcinoma: patients at high-risk for local recurrence treated with surgery and adjuvant chemoradiation have an equivalent overall survival to patients with standard-risk treated with surgery alone.
abstract: BACKGROUND
  Patients with resected extrahepatic bile duct adenocarcinoma who have microscopically positive resection margins and/or pathologic locoregional nodal involvement (R1pN1) have a high-risk of locoregional recurrence, and therefore, we advocate the use of adjuvant chemoradiation. To evaluate the safety and effectiveness of this treatment, we compared survival and side effects outcomes between such patients and patients with negative resection margins and pathologically negative nodes (R0pN0) who did not receive adjuvant treatment.
  
  
  METHODS
  Between 1984 and 2005, 65 patients were treated with curative-intended resection for extrahepatic bile duct adenocarcinoma. Patients with tumors arising in the gallbladder and periampullary region were excluded. Pathology and diagnostic images were centrally reviewed. Overall survival and locoregional recurrence outcomes for patients with standard-risk R0pN0 (surgery alone, or S group, n = 23) were compared with those of patients with high locoregional recurrence risk, R1 and/or pN1 (R1pN1) status who received adjuvant chemoradiation (S-CRT group, n = 42).
  
  
  RESULTS
  The median follow-up for the entire group was 31 months. Patients in the S-CRT and S groups had a similar 5-year overall survival (36% vs. 42%, P = .6) and locoregional recurrence (5-year rate: 38% vs. 37%, P = .13). In the S-CRT group, three patients (7%) experienced an acute (grade 3 or more) side effect.
  
  
  CONCLUSIONS
  Our finding of a lack of a survival difference between the S and S-CRT groups suggests that for patients with extrahepatic bile duct adenocarcinoma at high risk for locoregional recurrence (i.e., R1 resection or pN1 disease), adjuvant chemoradiation provides an equivalent overall survival despite of these worse prognostic features.
authors.affiliation: Department of Radiation Oncology, The University of Texas M D Anderson Cancer Center, 1515 Holcombe Blvd., Unit 97, Houston, TX 77030, USA. yborghero@yahoo.com
authors.forename: Yerko
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authors.lastname: Borghero
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authors.forename: Melanie B
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authors.forename: Jean-Nicolas
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authors.lastname: Vauthey