title: Pulmonary function changes after radiotherapy in non-small-cell lung cancer patients with long-term disease-free survival.
abstract: OBJECTIVE
  To evaluate the changes in pulmonary function after high-dose radiotherapy (RT) for non-small-cell lung cancer in patients with a long-term disease-free survival.
  
  
  METHODS
  Pulmonary function was measured in 34 patients with inoperable non-small-cell lung cancer before RT and at 3 and 18 months of follow-up. Thirteen of these patients had a pulmonary function test (PFT) 36 months after RT. The pulmonary function parameters (forced expiratory volume in 1 s [FEV(1)], diffusion capacity [T(lcoc)], forced vital capacity, and alveolar volume) were expressed as a percentage of normal values. Changes were expressed as relative to the pre-RT value. We evaluated the impact of chronic obstructive pulmonary disease, radiation pneumonitis, mean lung dose, and PFT results before RT on the changes in pulmonary function.
  
  
  RESULTS
  At 3, 18, and 36 months, a significant decrease was observed for the T(lcoc) (9.5%, 14.6%, and 22.0%, respectively) and the alveolar volume (5.8%, 6.6%, and 15.8%, respectively). The decrease in FEV(1) was significant at 18 and 36 months (8.8% and 13.4%, respectively). No recovery of any of the parameters was observed. Chronic obstructive pulmonary disease was an important risk factor for larger PFT decreases. FEV(1) and T(lcoc) decreases were dependent on the mean lung dose.
  
  
  CONCLUSIONS
  A significant decrease in pulmonary function was observed 3 months after RT. No recovery in pulmonary function was seen at 18 and 36 months after RT. The decrease in pulmonary function was dependent on the mean lung dose, and patients with chronic obstructive pulmonary disease had larger reductions in the PFTs.
authors.affiliation: Department of Radiation Oncology, The Netherlands Cancer Institute-Antoni van Leeuwenhoek Hospital, Amsterdam, The Netherlands.
authors.forename: Gerben R
authors.initials: GR
authors.lastname: Borst
authors.forename: Katrien
authors.initials: K
authors.lastname: De Jaeger
authors.forename: José S A
authors.initials: JS
authors.lastname: Belderbos
authors.forename: Sjaak A
authors.initials: SA
authors.lastname: Burgers
authors.forename: Joos V
authors.initials: JV
authors.lastname: Lebesque
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002289:Carcinoma, Non-Small-Cell Lung / Q000503:physiopathology* / Q000532:radiotherapy*; D018572:Disease-Free Survival; D005260:Female; D005541:Forced Expiratory Volume / Q000528:radiation effects; D006801:Humans; D008175:Lung Neoplasms / Q000503:physiopathology* / Q000532:radiotherapy*; D008297:Male; D008875:Middle Aged; D011653:Pulmonary Diffusing Capacity / Q000528:radiation effects; D029424:Pulmonary Disease, Chronic Obstructive / Q000503:physiopathology; D017564:Radiation Pneumonitis / Q000503:physiopathology; D014797:Vital Capacity / Q000528:radiation effects