title: Changes in pulmonary function after definitive radiotherapy for NSCLC.
abstract: BACKGROUND
  The objective of this study was to identify factors associated with early and long-term pulmonary function (PF) changes after definitive radiotherapy for NSCLC patients. PF was measured by spirometry i.e. forced expiratory volume in 1s (FEV1), and forced vital capacity (FVC).
  
  
  METHODS
  Early (within the first year) PF change was analyzed in 211 patients with 986 pairs of PF-tests (PFTs). Long-term PF change was analyzed relative to the PF at 12months after radiotherapy in 106 patients (1286 PFTs). To investigate the impact of patient and treatment related factors on PF, they were tested as covariates in multivariable analysis.
  
  
  RESULTS
  Early PF change was quantified at six months after the start of radiotherapy. Smoking status and increasing V60 was associated with a significant decrease in PF, whereas smoking was protective. In addition, neoadjuvant chemotherapy had a negative impact on FVC. Long-term FEV1 and FVC were analyzed using linear regression. Treatment year and V60 had a significant impact on loss of FEV1. V60 had a significant impact on FVC changes.
  
  
  CONCLUSIONS
  In this study, early PF change reached a plateau at 6months after the start of radiotherapy for NSCLC. Large volume of lung receiving high dose was associated with long-term FEV1 change.
authors.affiliation: Department of Oncology, Odense University Hospital, Denmark; Institute of Clinical Research, University of Southern Denmark, Denmark.
authors.forename: Tine
authors.initials: T
authors.lastname: Schytte
authors.affiliation: Division of Biostatistics and Bioinformatics, University of Maryland Greenebaum Cancer Center and Department of Epidemiology and Public Health, University of Maryland School of Medicine, Baltimore, USA.
authors.forename: Søren M
authors.initials: SM
authors.lastname: Bentzen
authors.affiliation: Laboratory of Radiation Physics, Odense University Hospital, Denmark; Institute of Clinical Research, University of Southern Denmark, Denmark.
authors.forename: Carsten
authors.initials: C
authors.lastname: Brink
authors.affiliation: Department of Oncology, Odense University Hospital, Denmark; Institute of Clinical Research, University of Southern Denmark, Denmark.
authors.forename: Olfred
authors.initials: O
authors.lastname: Hansen
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002289:Carcinoma, Non-Small-Cell Lung / Q000532:radiotherapy*; D005260:Female; D005541:Forced Expiratory Volume; D006801:Humans; D008168:Lung / Q000503:physiopathology* / Q000528:radiation effects*; D008175:Lung Neoplasms / Q000532:radiotherapy*; D008297:Male; D008875:Middle Aged; D012129:Respiratory Function Tests
keywords: Definitive radiotherapy; Early and long-term changes; NSCLC; Pulmonary function