title: Multifield optimization intensity modulated proton therapy for head and neck tumors: a translation to practice.
abstract: BACKGROUND
  We report the first clinical experience and toxicity of multifield optimization (MFO) intensity modulated proton therapy (IMPT) for patients with head and neck tumors.
  
  
  METHODS
  Fifteen consecutive patients with head and neck cancer underwent MFO-IMPT with active scanning beam proton therapy. Patients with squamous cell carcinoma (SCC) had comprehensive treatment extending from the base of the skull to the clavicle. The doses for chemoradiation therapy and radiation therapy alone were 70 Gy and 66 Gy, respectively. The robustness of each treatment plan was also analyzed to evaluate sensitivity to uncertainties associated with variations in patient setup and the effect of uncertainties with proton beam range in patients. Proton beam energies during treatment ranged from 72.5 to 221.8 MeV. Spot sizes varied depending on the beam energy and depth of the target, and the scanning nozzle delivered the spot scanning treatment "spot by spot" and "layer by layer."
  
  
  RESULTS
  Ten patients presented with SCC and 5 with adenoid cystic carcinoma. All 15 patients were able to complete treatment with MFO-IMPT, with no need for treatment breaks and no hospitalizations. There were no treatment-related deaths, and with a median follow-up time of 28 months (range, 20-35 months), the overall clinical complete response rate was 93.3% (95% confidence interval, 68.1%-99.8%). Xerostomia occurred in all 15 patients as follows: grade 1 in 10 patients, grade 2 in 4 patients, and grade 3 in 1 patient. Mucositis within the planning target volumes was seen during the treatment of all patients: grade 1 in 1 patient, grade 2 in 8 patients, and grade 3 in 6 patients. No patient experienced grade 2 or higher anterior oral mucositis.
  
  
  CONCLUSIONS
  To our knowledge, this is the first clinical report of MFO-IMPT for head and neck tumors. Early clinical outcomes are encouraging and warrant further investigation of proton therapy in prospective clinical trials.
authors.affiliation: Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas. Electronic address: sjfrank@mdanderson.org.
authors.forename: Steven J
authors.initials: SJ
authors.lastname: Frank
authors.affiliation: Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas.
authors.forename: James D
authors.initials: JD
authors.lastname: Cox
authors.affiliation: Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas.
authors.forename: Michael
authors.initials: M
authors.lastname: Gillin
authors.affiliation: Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas.
authors.forename: Radhe
authors.initials: R
authors.lastname: Mohan
authors.affiliation: Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas.
authors.forename: Adam S
authors.initials: AS
authors.lastname: Garden
authors.affiliation: Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas.
authors.forename: David I
authors.initials: DI
authors.lastname: Rosenthal
authors.affiliation: Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas.
authors.forename: G Brandon
authors.initials: GB
authors.lastname: Gunn
authors.affiliation: Department of Head and Neck Surgery, The University of Texas MD Anderson Cancer Center, Houston, Texas.
authors.forename: Randal S
authors.initials: RS
authors.lastname: Weber
authors.affiliation: Department of Head and Neck Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas.
authors.forename: Merrill S
authors.initials: MS
authors.lastname: Kies
authors.affiliation: Department of Head and Neck Surgery, The University of Texas MD Anderson Cancer Center, Houston, Texas.
authors.forename: Jan S
authors.initials: JS
authors.lastname: Lewin
authors.affiliation: Department of Biostatistics, The University of Texas MD Anderson Cancer Center, Houston, Texas.
authors.forename: Mark F
authors.initials: MF
authors.lastname: Munsell
authors.affiliation: Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas.
authors.forename: Matthew B
authors.initials: MB
authors.lastname: Palmer
authors.affiliation: Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas.
authors.forename: Narayan
authors.initials: N
authors.lastname: Sahoo
authors.affiliation: Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas.
authors.forename: Xiaodong
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas.
authors.forename: Wei
authors.initials: W
authors.lastname: Liu
authors.affiliation: Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas.
authors.forename: X Ronald
authors.initials: XR
authors.lastname: Zhu
mesh_terms: D000328:Adult; D000368:Aged; D003528:Carcinoma, Adenoid Cystic / Q000188:drug therapy / Q000532:radiotherapy*; D002294:Carcinoma, Squamous Cell / Q000188:drug therapy / Q000532:radiotherapy*; D059248:Chemoradiotherapy; D005260:Female; D005500:Follow-Up Studies; D006258:Head and Neck Neoplasms / Q000188:drug therapy / Q000532:radiotherapy*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009303:Nasopharyngeal Neoplasms / Q000188:drug therapy / Q000532:radiotherapy; D009959:Oropharyngeal Neoplasms / Q000188:drug therapy / Q000532:radiotherapy; D010865:Pilot Projects; D061766:Proton Therapy / Q000009:adverse effects / Q000379:methods*; D011785:Quality Assurance, Health Care; D011879:Radiotherapy Dosage; D011880:Radiotherapy Planning, Computer-Assisted; D061106:Radiotherapy Setup Errors; D050397:Radiotherapy, Intensity-Modulated / Q000009:adverse effects / Q000379:methods*; D013280:Stomatitis / Q000209:etiology; D014062:Tongue Neoplasms / Q000188:drug therapy / Q000532:radiotherapy; D035501:Uncertainty; D014987:Xerostomia / Q000209:etiology