title: Adaptive radiotherapy for head-and-neck cancer: initial clinical outcomes from a prospective trial.
abstract: OBJECTIVE
  To present pilot toxicity and survival outcomes for a prospective trial investigating adaptive radiotherapy (ART) for oropharyngeal squamous cell carcinoma.
  
  
  METHODS
  A total of 24 patients were enrolled in an institutional review board-approved clinical trial; data for 22 of these patients were analyzed. Daily CT-guided setup and deformable image registration permitted serial mapping of clinical target volumes and avoidance structures for ART planning. Primary site was base of tongue in 15 patients, tonsil in 6 patient, and glossopharyngeal sulcus in 1 patient. Twenty patients (91%) had American Joint Committee on Cancer (AJCC) Stage IV disease. T stage distribution was 2 T1, 12 T2, 3 T3, 5 T4. N stage distribution was 1 N0, 2 N1, 5 N2a, 12 N2b, and 2 N2c. Of the patients, 21 (95%) received systemic therapy.
  
  
  RESULTS
  With a 31-month median follow-up (range, 13-45 months), there has been no primary site failure and 1 nodal relapse, yielding 100% local and 95% regional disease control at 2 years. Baseline tumor size correlated with absolute volumetric treatment response (p = 0.018). Parotid volumetric change correlated with duration of feeding tube placement (p = 0.025). Acute toxicity was comparable to that observed with conventional intensity-modulated radiotherapy (IMRT). Chronic toxicity and functional outcomes beyond 1 year were tabulated.
  
  
  CONCLUSIONS
  This is the first prospective evaluation of morbidity and survival outcomes in patients with locally advanced head-and-neck cancer treated with automated adaptive replanning. ART can provide dosimetric benefit with only one or two mid-treatment replanning events. Our preliminary clinical outcomes document functional recovery and preservation of disease control at 1-year follow-up and beyond.
authors.affiliation: Department of Radiation Medicine, Hofstra North Shore-Long Island Jewish School of Medicine, New Hyde Park, NY 11040, USA. dschwartz3@nshs.edu
authors.forename: David L
authors.initials: DL
authors.lastname: Schwartz
authors.forename: Adam S
authors.initials: AS
authors.lastname: Garden
authors.forename: Jimmy
authors.initials: J
authors.lastname: Thomas
authors.forename: Yipei
authors.initials: Y
authors.lastname: Chen
authors.forename: Yongbin
authors.initials: Y
authors.lastname: Zhang
authors.forename: Jan
authors.initials: J
authors.lastname: Lewin
authors.forename: Mark S
authors.initials: MS
authors.lastname: Chambers
authors.forename: Lei
authors.initials: L
authors.lastname: Dong
mesh_terms: D000328:Adult; D000368:Aged; D002294:Carcinoma, Squamous Cell / Q000000981:diagnostic imaging / Q000473:pathology / Q000532:radiotherapy*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging / Q000379:methods; D058958:Organs at Risk / Q000000981:diagnostic imaging; D009959:Oropharyngeal Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology / Q000532:radiotherapy*; D011446:Prospective Studies; D011880:Radiotherapy Planning, Computer-Assisted / Q000379:methods*; D061106:Radiotherapy Setup Errors / Q000517:prevention & control; D061089:Radiotherapy, Image-Guided / Q000009:adverse effects / Q000379:methods*; D050397:Radiotherapy, Intensity-Modulated / Q000009:adverse effects / Q000379:methods*; D014057:Tomography, X-Ray Computed / Q000379:methods; D014062:Tongue Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology / Q000532:radiotherapy; D014067:Tonsillar Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology / Q000532:radiotherapy; D047368:Tumor Burden