title: Prospective study of proton beam radiation therapy for adjuvant and definitive treatment of thymoma and thymic carcinoma: Early response and toxicity assessment.
abstract: OBJECTIVE
  Radiation is an important modality in treatment of thymic tumors. However, toxicity may reduce its overall benefit. We hypothesized that double-scattering proton beam therapy (DS-PT) can achieve excellent local control with limited toxicity in patients with thymic malignancies.
  
  
  METHODS
  Patients with thymoma or thymic carcinoma treated with DS-PT between 2011 and 2015 were prospectively analyzed for toxicity and patterns of failure on an IRB-approved study.
  
  
  RESULTS
  Twenty-seven consecutive patients were evaluated. Patients were a median of 56 years and had thymoma (85%). They were treated with definitive (22%), salvage (15%) or adjuvant (63%) DS-PT to a median of 61.2/1.8 Gy [CGE]. No patient experienced grade ⩾3 toxicity. Acute grade 2 toxicities included dermatitis (37%), fatigue (11%), esophagitis (7%), and pneumonitis (4%). Late grade 2 toxicity was limited to a single patient with chronic dyspnea. At a median follow-up of 2 years, 100% local control was achieved. Three-year regional control, distant control, and overall survival rates were 96% (95% CI 76-99%), 74% (95% CI 41-90%), and 94% (95% CI 63-99%), respectively.
  
  
  CONCLUSIONS
  This is the first cohort and prospective series of proton therapy to treat thymic tumors, demonstrating low rates of early toxicity and excellent initial outcomes.
authors.affiliation: Hospital of the University of Pennsylvania, Department of Radiation Oncology, Philadelphia, United States. Electronic address: jennifer.vogel@uphs.upenn.edu.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Vogel
authors.affiliation: Hospital of the University of Pennsylvania, Department of Radiation Oncology, Philadelphia, United States.
authors.forename: Abigail T
authors.initials: AT
authors.lastname: Berman
authors.affiliation: Hospital of the University of Pennsylvania, Department of Radiation Oncology, Philadelphia, United States.
authors.forename: Liyong
authors.initials: L
authors.lastname: Lin
authors.affiliation: Penn Presbyterian Medical Center, Department of Thoracic Surgery, Philadelphia, United States.
authors.forename: Taine T
authors.initials: TT
authors.lastname: Pechet
authors.affiliation: Hospital of the University of Pennsylvania, Department of Radiation Oncology, Philadelphia, United States.
authors.forename: William P
authors.initials: WP
authors.lastname: Levin
authors.affiliation: Hospital of the University of Pennsylvania, Department of Radiation Oncology, Philadelphia, United States.
authors.forename: Peter
authors.initials: P
authors.lastname: Gabriel
authors.affiliation: Penn Presbyterian Medical Center, Department of Neurology, Philadelphia, United States.
authors.forename: Sami L
authors.initials: SL
authors.lastname: Khella
authors.affiliation: Hospital of the University of Pennsylvania, Department of Thoracic Surgery, Philadelphia, United States.
authors.forename: Sunil
authors.initials: S
authors.lastname: Singhal
authors.affiliation: Hospital of the University of Pennsylvania, Department of Thoracic Surgery, Philadelphia, United States.
authors.forename: John K
authors.initials: JK
authors.lastname: Kucharczuk
authors.affiliation: Hospital of the University of Pennsylvania, Department of Radiation Oncology, Philadelphia, United States.
authors.forename: Charles B
authors.initials: CB
authors.lastname: Simone
mesh_terms: D000368:Aged; D015331:Cohort Studies; D005260:Female; D056973:Four-Dimensional Computed Tomography / Q000379:methods; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D061766:Proton Therapy / Q000009:adverse effects* / Q000379:methods*; D011522:Protons / Q000009:adverse effects*; D011880:Radiotherapy Planning, Computer-Assisted / Q000379:methods; D015996:Survival Rate; D013945:Thymoma / Q000532:radiotherapy*; D013953:Thymus Neoplasms / Q000532:radiotherapy*
chemical_list: D011522:Protons
keywords: Cardiac toxicity; Proton therapy; Thymic carcinoma; Thymoma