title: Radiation pneumonitis and pulmonary function with lung dose-volume constraints in breast cancer irradiation.
abstract: OBJECTIVE
  We studied symptomatic radiation pneumonitis (RP) and changes in pulmonary function tests (PFTs) after loco-regional radiotherapy (LRRT) withV20lung constraints in breast cancer (BC).
  
  
  METHODS
  Sixty-four women underwent PFTs before and 5 months after 3D planned LRRT for BC. The incidentally irradiated ipsilateral lungV20was minimised to <30%. Patients were monitored for symptoms of RP 1, 4 and 7 months after radiotherapy (RT) and data on covariates were collected prospectively. The outcome was compared with previous treatment series.
  
  
  RESULTS
  Pneumonitis was less frequent with the applied constraint, that is, four mild and one moderate case, than in our previous report (p< 0·001). In multivariate analyses, neither dosimetric data nor covariates appeared to influence mean changes in vital capacity [-0·11L, standard error of the mean (SEM) 0·03] or diffusing capacity of the lung for carbon monoxide (DLCO) (-0·20 mmol/kPa/min, SEM 0·01), except for pre-RT chemotherapy, which diminished the change in DLCO 5 months post-RT.
  
  
  CONCLUSIONS
  The used constraint and 3D planning lowered the rate of RP and short-term changes in PFTs compared with our previous treatment series. Pre-RT chemotherapy affects DLCO baseline levels. Rates of side effects should be continuously studied when new target definitions or therapies are introduced in LRRT of BC.
authors.affiliation: Department of Oncology , Karolinska University Hospital, Stockholm , Sweden ; Department of Oncology-Pathology , Karolinska Institutet , Stockholm , Sweden.
authors.forename: U
authors.initials: U
authors.lastname: Blom Goldman
authors.affiliation: Department of Physiology , Stockholm Söder Hospital , Stockholm , Sweden.
authors.forename: M
authors.initials: M
authors.lastname: Anderson
authors.affiliation: Department of Medical Physics , Karolinska University Hospital , Stockholm , Sweden.
authors.forename: B
authors.initials: B
authors.lastname: Wennberg
authors.affiliation: Department of Oncology-Pathology , Karolinska Institutet , Stockholm , Sweden ; Department of Oncology Sörmland , Mälarsjukhuset , Eskilstuna , Sweden.
authors.forename: P
authors.initials: P
authors.lastname: Lind
keywords: breast cancer; dose–volume histogram; loco-regional radiotherapy; pulmonary function; radiation pneumonitis; radiotherapy