title: Clinical outcomes among patients with head and neck cancer treated by intensity-modulated radiotherapy with and without adaptive replanning.
abstract: BACKGROUND
  The purpose of this study was to determine the effect of adaptive replanning on clinical outcome among patients treated by intensity-modulated radiotherapy (IMRT) for head and neck cancer.
  
  
  METHODS
  Three hundred seventeen patients underwent IMRT with daily image-guidance for newly diagnosed squamous cell carcinoma of the head and neck to a median dose of 66 Gy (range, 60-74 Gy). Of these 317 patients, 51 (16%) underwent adaptive radiotherapy with modification of the original IMRT midway during treatment.
  
  
  RESULTS
  The 2-year local-regional control was 88% for patients treated with adaptive replanning compared with 79% for patients treated without (p = .01). The median time to local-regional recurrence for the 4 patients treated by adaptive radiotherapy was 7 months (range, 3-15 months) with all failures occurring within the high-dose planning target volume (PTV).
  
  
  CONCLUSIONS
  Although the use of routine replanning is probably not necessary, our findings do suggest a significant benefit in appropriately selected patients.
authors.affiliation: Department of Radiation Oncology, University of California Davis Comprehensive Cancer Center, Sacramento, California.
authors.forename: Allen M
authors.initials: AM
authors.lastname: Chen
authors.forename: Megan E
authors.initials: ME
authors.lastname: Daly
authors.forename: Jing
authors.initials: J
authors.lastname: Cui
authors.forename: Mathew
authors.initials: M
authors.lastname: Mathai
authors.forename: Stanley
authors.initials: S
authors.lastname: Benedict
authors.forename: James A
authors.initials: JA
authors.lastname: Purdy
mesh_terms: D000368:Aged; D002294:Carcinoma, Squamous Cell / Q000175:diagnosis / Q000401:mortality* / Q000532:radiotherapy*; D015331:Cohort Studies; D018572:Disease-Free Survival; D004307:Dose-Response Relationship, Radiation; D005260:Female; D006258:Head and Neck Neoplasms / Q000175:diagnosis / Q000401:mortality* / Q000532:radiotherapy*; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D011879:Radiotherapy Dosage; D011880:Radiotherapy Planning, Computer-Assisted; D050397:Radiotherapy, Intensity-Modulated / Q000009:adverse effects / Q000379:methods*; D012189:Retrospective Studies; D018570:Risk Assessment; D000077195:Squamous Cell Carcinoma of Head and Neck; D016019:Survival Analysis; D016896:Treatment Outcome
keywords: adaptive radiotherapy; head and neck cancer; image-guidance; intensity-modulated radiotherapy (IMRT); outcomes