title: Proton therapy for head and neck adenoid cystic carcinoma: initial clinical outcomes.
abstract: BACKGROUND
  The purpose of this study was to report outcomes of proton therapy in head and neck adenoid cystic carcinoma.
  
  
  METHODS
  We conducted a retrospective analysis of 26 patients treated between 2004 and 2012. Twenty patients (77%) had base of skull involvement; 19 (73%) were treated for initial disease and 7 (27%) for recurrent disease. Twenty patients were treated postoperatively, 6 after biopsy alone and 24 had positive margins or gross residual disease.Median dose delivered was 72 Gy (relative biological effectiveness[RBE]).
  
  
  RESULTS
  Median follow-up was 25 months (range, 7–50 months). The 2-year overall survival was 93% for initial disease course and 57% for recurrent disease (p5.19). The 2-year local control was 95% for initial disease and 86% for recurrent disease (p5.48). The 2-year distant metastatic rate was 25%. Late toxicity of grade 0 or 1 was seen in 17 patients, grade 2 in 5, grade 3 in 2, grade 4 in 1, and grade 5 in 1.
  
  
  CONCLUSIONS
  Initial outcomes of proton therapy are encouraging. Longer follow-up is required.
authors: Okechukwu R
authors: OR
authors: Linton
authors: Michael G
authors: MG
authors: Moore
authors: Joseph S
authors: JS
authors: Brigance
authors: Don-John
authors: DJ
authors: Summerlin
authors: Mark W
authors: MW
authors: McDonald
mesh_terms: D000328:Adult; D000368:Aged; D003528:Carcinoma, Adenoid Cystic / Q000401:mortality / Q000473:pathology / Q000532:radiotherapy*; D018572:Disease-Free Survival; D005260:Female; D005500:Follow-Up Studies; D006258:Head and Neck Neoplasms / Q000401:mortality / Q000473:pathology / Q000532:radiotherapy*; D006801:Humans; D008297:Male; D008875:Middle Aged; D061766:Proton Therapy; D011879:Radiotherapy Dosage; D012189:Retrospective Studies; D015996:Survival Rate; D016896:Treatment Outcome; D055815:Young Adult