title: Feasibility of proton beam therapy for reirradiation of locoregionally recurrent non-small cell lung cancer.
abstract: OBJECTIVE
  Options are limited for patients with intrathoracic recurrence of non-small cell lung cancer (NSCLC) who previously received radiation. We report our 5-year experience with the toxicity and efficacy of proton beam therapy (PBT) for reirradiation.
  
  
  METHODS
  Thirty-three patients underwent PBT reirradiation for intrathoracic recurrent NSCLC at a single institution. All patients had had RT for NSCLC (median initial dose 63 Gy in 33 fractions), with median interval to reirradiation of 36 months. Median reirradiation dose was 66 Gy (RBE) in 32 fractions. Toxicity was scored with CTCAE v4.0, and survival outcomes were estimated using Kaplan-Meier.
  
  
  RESULTS
  Thirty-one patients (94%) completed reirradiation. At a median 11 months' follow-up, 1-year rates of overall survival, progression-free survival, locoregional control, and distant metastasis-free survival were 47%, 28%, 54%, and 39%. Rates of severe (grade ≥3) toxicity were 9% esophageal, 21% pulmonary; 1 patient had grade 4 esophagitis, and 2 had grade 4 pulmonary toxicity. Nine patients experienced a second in-field failure.
  
  
  CONCLUSIONS
  PBT is an option for treating recurrent NSCLC. However, the rates of locoregional recurrence and distant metastasis are high and the potential for toxicity significant. The risks and benefits of PBT must be carefully weighed in each case.
authors.affiliation: Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, United States.
authors.forename: Sarah A
authors.initials: SA
authors.lastname: McAvoy
authors.forename: Katherine T
authors.initials: KT
authors.lastname: Ciura
authors.forename: Justin M
authors.initials: JM
authors.lastname: Rineer
authors.forename: Pamela K
authors.initials: PK
authors.lastname: Allen
authors.forename: Zhongxing
authors.initials: Z
authors.lastname: Liao
authors.forename: Joe Y
authors.initials: JY
authors.lastname: Chang
authors.forename: Matthew B
authors.initials: MB
authors.lastname: Palmer
authors.forename: James D
authors.initials: JD
authors.lastname: Cox
authors.forename: Ritsuko
authors.initials: R
authors.lastname: Komaki
authors.forename: Daniel R
authors.initials: DR
authors.lastname: Gomez
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002289:Carcinoma, Non-Small-Cell Lung / Q000401:mortality / Q000473:pathology / Q000532:radiotherapy*; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000401:mortality / Q000473:pathology / Q000532:radiotherapy*; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000532:radiotherapy*; D009367:Neoplasm Staging; D061766:Proton Therapy / Q000009:adverse effects; D012189:Retrospective Studies; D047368:Tumor Burden
keywords: Non small cell lung cancer; Proton beam radiotherapy; Reirradiation