title: Pulmonary function and quality of life after VMAT-based stereotactic ablative radiotherapy for early stage inoperable NSCLC: a prospective study.
abstract: OBJECTIVE
  To analyze changes in pulmonary function and quality of life (QoL) at different time points after Stereotactic Ablative Radiotherapy (SABR) for early stage inoperable lung cancer, and potential correlations between radiation dose-volume parameters and pulmonary toxicity or changes in pulmonary function tests (PFT) and QoL.
  
  
  METHODS
  From July 2012 to October 2013, 30 patients were enrolled in this prospective observational study. Complete PFT were performed and Lung Cancer Symptoms Scale (LCSS) questionnaire administered prior to SABR; all patients then underwent Computed Tomography (CT) scan and PFT at 45, 135, 225 and 315 days after SABR, together with LCSS questionnaire. Clinical lung toxicity and radiological toxicity (acute and late) were prospectively recorded by using the Radiation Therapy Oncology Group (RTOG) scoring system.
  
  
  RESULTS
  A decline in Slow Vital Capacity (SVC), Forced Expiratory Volume in 1s (FEV1), Single-breath lung diffusing capacity (DLCO) and blood partial pressure of oxygen (PaO2) was seen at 135 days post-SABR. PaO2 values rescued to normal levels at 315 days. None of the baseline PFT parameters resulted to be associated with the occurrence of pulmonary toxicity or with late radiological changes. Mean V5, V10, and V20 and MLD2Gy were higher in patients who developed radiation pneumonitis, even if not significantly associated at Cox regression analysis. LCSS QoL showed a significant worsening of the single item fatigue at 135 days after SABR.
  
  
  CONCLUSIONS
  A small (mean 10%) but significant decline in lung volumes and DLCO was recorded after SABR, with clinical impact of such change difficult to estimate in individual patients. Global QoL was not significantly impaired. Dose-volume parameters did not emerge as significantly predictive of any clinical, radiological or functional toxicity.
authors.affiliation: Respiratory Function and Sleep Laboratory, S. Luigi Hospital, Orbassano, Italy.
authors.forename: Cinzia
authors.initials: C
authors.lastname: Ferrero
authors.affiliation: Department of Oncology, University of Torino, Torino, Italy.
authors.forename: Serena
authors.initials: S
authors.lastname: Badellino
authors.affiliation: Department of Oncology, University of Torino, Torino, Italy. Electronic address: andreariccardo.filippi@unito.it.
authors.forename: Andrea Riccardo
authors.initials: AR
authors.lastname: Filippi
authors.affiliation: Department of Oncology, University of Torino, Torino, Italy.
authors.forename: Luana
authors.initials: L
authors.lastname: Focaraccio
authors.affiliation: Department of Oncology, University of Torino, Torino, Italy.
authors.forename: Matteo
authors.initials: M
authors.lastname: Giaj Levra
authors.affiliation: Department of Oncology, University of Torino, Torino, Italy.
authors.forename: Mario
authors.initials: M
authors.lastname: Levis
authors.affiliation: Department of Oncology, University of Torino, Torino, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Moretto
authors.affiliation: Respiratory Function and Sleep Laboratory, S. Luigi Hospital, Orbassano, Italy.
authors.forename: Roberto
authors.initials: R
authors.lastname: Torchio
authors.affiliation: Department of Oncology, University of Torino, Torino, Italy.
authors.forename: Umberto
authors.initials: U
authors.lastname: Ricardi
authors.affiliation: Department of Oncology, University of Torino, Torino, Italy.
authors.forename: Silvia
authors.initials: S
authors.lastname: Novello
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002289:Carcinoma, Non-Small-Cell Lung / Q000453:epidemiology* / Q000473:pathology / Q000503:physiopathology* / Q000601:surgery; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008175:Lung Neoplasms / Q000453:epidemiology* / Q000473:pathology / Q000503:physiopathology* / Q000601:surgery; D008875:Middle Aged; D009367:Neoplasm Staging; D011446:Prospective Studies; D011788:Quality of Life; D016634:Radiosurgery / Q000009:adverse effects / Q000379:methods; D012129:Respiratory Function Tests; D012307:Risk Factors; D016896:Treatment Outcome
keywords: Early stage; Lung cancer; Pulmonary function; Radiation pneumonitis; Stereotactic ablative radiotherapy; Stereotactic body radiotherapy