title: Hemithoracic intensity modulated radiation therapy after pleurectomy/decortication for malignant pleural mesothelioma: toxicity, patterns of failure, and a matched survival analysis.
abstract: OBJECTIVE
  To investigate safety, efficacy, and recurrence after hemithoracic intensity modulated radiation therapy after pleurectomy/decortication (PD-IMRT) and after extrapleural pneumonectomy (EPP-IMRT).
  
  
  METHODS
  In 2009-2013, 24 patients with mesothelioma underwent PD-IMRT to the involved hemithorax to a dose of 45 Gy, with an optional integrated boost; 22 also received chemotherapy. Toxicity was scored with the Common Terminology Criteria for Adverse Events v4.0. Pulmonary function was compared at baseline, after surgery, and after IMRT. Kaplan-Meier analysis was used to calculate overall survival (OS), progression-free survival (PFS), time to locoregional failure, and time to distant metastasis. Failures were in-field, marginal, or out of field. Outcomes were compared with those of 24 patients, matched for age, nodal status, performance status, and chemotherapy, who had received EPP-IMRT.
  
  
  RESULTS
  Median follow-up time was 12.2 months. Grade 3 toxicity rates were 8% skin and 8% pulmonary. Pulmonary function declined from baseline to after surgery (by 21% for forced vital capacity, 16% for forced expiratory volume in 1 second, and 19% for lung diffusion of carbon monoxide [P for all = .01]) and declined still further after IMRT (by 31% for forced vital capacity [P=.02], 25% for forced expiratory volume in 1 second [P=.01], and 30% for lung diffusion of carbon monoxide [P=.01]). The OS and PFS rates were 76% and 67%, respectively, at 1 year and 56% and 34% at 2 years. Median OS (28.4 vs 14.2 months, P=.04) and median PFS (16.4 vs 8.2 months, P=.01) favored PD-IMRT versus EPP-IMRT. No differences were found in grade 4-5 toxicity (0 of 24 vs 3 of 24, P=.23), median time to locoregional failure (18.7 months vs not reached, P not calculable), or median time to distant metastasis (18.8 vs 11.8 months, P=.12).
  
  
  CONCLUSIONS
  Hemithoracic intensity modulated radiation therapy after pleurectomy/decortication produced little high-grade toxicity but led to progressive declines in pulmonary function; OS and PFS were better in PD-IMRT compared with EPP-IMRT.
authors.affiliation: Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas.
authors.forename: William W
authors.initials: WW
authors.lastname: Chance
authors.affiliation: Department of Thoracic and Cardiovascular Surgery, The University of Texas MD Anderson Cancer Center, Houston, Texas.
authors.forename: David C
authors.initials: DC
authors.lastname: Rice
authors.affiliation: Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas.
authors.forename: Pamela K
authors.initials: PK
authors.lastname: Allen
authors.affiliation: Department of Thoracic/Head and Neck Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas.
authors.forename: Anne S
authors.initials: AS
authors.lastname: Tsao
authors.affiliation: Princeton Radiation Oncology, Monroe Township, New Jersey.
authors.forename: Hiral P
authors.initials: HP
authors.lastname: Fontanilla
authors.affiliation: Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas.
authors.forename: Zhongxing
authors.initials: Z
authors.lastname: Liao
authors.affiliation: Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas.
authors.forename: Joe Y
authors.initials: JY
authors.lastname: Chang
authors.affiliation: Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas.
authors.forename: Chad
authors.initials: C
authors.lastname: Tang
authors.affiliation: Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas.
authors.forename: Hubert Y
authors.initials: HY
authors.lastname: Pan
authors.affiliation: Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas.
authors.forename: James W
authors.initials: JW
authors.lastname: Welsh
authors.affiliation: Department of Thoracic and Cardiovascular Surgery, The University of Texas MD Anderson Cancer Center, Houston, Texas.
authors.forename: Reza J
authors.initials: RJ
authors.lastname: Mehran
authors.affiliation: Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas. Electronic address: dgomez@mdanderson.org.
authors.forename: Daniel R
authors.initials: DR
authors.lastname: Gomez
mesh_terms: D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D003131:Combined Modality Therapy / Q000009:adverse effects / Q000379:methods / Q000401:mortality; D018572:Disease-Free Survival; D005260:Female; D056973:Four-Dimensional Computed Tomography; D041981:Gastrointestinal Tract / Q000528:radiation effects; D006801:Humans; D008168:Lung / Q000503:physiopathology / Q000528:radiation effects; D008175:Lung Neoplasms / Q000401:mortality / Q000532:radiotherapy* / Q000556:secondary / Q000601:surgery; D008297:Male; D008654:Mesothelioma / Q000401:mortality / Q000532:radiotherapy* / Q000556:secondary / Q000601:surgery; D000086002:Mesothelioma, Malignant; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local; D010994:Pleura / Q000601:surgery*; D010997:Pleural Neoplasms / Q000401:mortality / Q000532:radiotherapy* / Q000601:surgery; D011013:Pneumonectomy / Q000379:methods*; D011182:Postoperative Care; D011832:Radiation Injuries / Q000473:pathology; D050397:Radiotherapy, Intensity-Modulated / Q000009:adverse effects / Q000379:methods* / Q000401:mortality; D012867:Skin / Q000528:radiation effects; D016019:Survival Analysis; D017211:Treatment Failure