title: Image-guided intensity-modulated radiotherapy (IG-IMRT) for biliary adenocarcinomas: Initial clinical results.
abstract: OBJECTIVE
  Biliary tract lesions are comparatively rare neoplasms, with ambiguous indications for radiotherapy. The specific aim of this study was to report the clinical results of a single-institution biliary tract series treated with modern radiotherapeutic techniques, and detail results using both conventional and image-guided intensity-modulated radiation therapy (IG-IMRT).
  
  
  METHODS
  From 2001 to 2005, 24 patients with primary adenocarcinoma of the biliary tract (gallbladder and extrahepatic bile ducts) were treated by IG-IMRT. To compare outcomes, data from a sequential series of 24 patients treated between 1995 and 2005 with conventional radiotherapy (CRT) techniques were collected as a comparator set. Demographic and treatment parameters were collected. Endpoints analyzed included treatment-related acute toxicity and survival.
  
  
  RESULTS
  Median estimated survival for all patients completing treatment was 13.9 months. A statistically significant higher mean dose was given to patients receiving IG-IMRT compared to CRT, 59 vs. 48Gy. IG-IMRT and CRT cohorts had a median survival of 17.6 and 9.0 months, respectively. Surgical resection was associated with improved survival. Two patients (4%) experienced an RTOG acute toxicity score>2. The most commonly reported GI toxicities (RTOG Grade 2) were nausea or diarrhea requiring oral medication, experienced by 46% of patients.
  
  
  CONCLUSIONS
  This series presents the first clinical outcomes of biliary tract cancers treated with IG-IMRT. In comparison to a cohort of patients treated by conventional radiation techniques, IG-IMRT was feasible for biliary tract tumors, warranting further investigation in prospective clinical trials.
authors.affiliation: Department of Radiation Oncology, The University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Drive, San Antonio, TX 78229, USA. fullercd@uthscsa.edu
authors.forename: Clifton David
authors.initials: CD
authors.lastname: Fuller
authors.forename: Nguyen Dinh
authors.initials: ND
authors.lastname: Dang
authors.forename: Samuel J
authors.initials: SJ
authors.lastname: Wang
authors.forename: Prashant
authors.initials: P
authors.lastname: Desai
authors.forename: Mehee
authors.initials: M
authors.lastname: Choi
authors.forename: Charles R
authors.initials: CR
authors.lastname: Thomas
authors.forename: Martin
authors.initials: M
authors.lastname: Fuss