title: Pulmonary complications following different radiotherapy techniques for breast cancer, and the association to irradiated lung volume and dose.
abstract: OBJECTIVE
  This study investigates the incidence of short-term pulmonary complications following radiotherapy (RT) for breast cancer (BC) with different treatment techniques/incidentally irradiated lung volumes and the importance of confounding factors on RT-induced pulmonary complications.
  
  
  METHODS
  Prospectively, 475 patients with BC were followed for pulmonary complications 1, 4 and 7 months post-RT. Mean lung dose volume histograms (MDVH) were constructed and compared for the different RT-techniques. Among a subset of the mastectomized patients treated with loco-regional (LR-) RT, who had undergone complete three-dimensional (3-D) dose planning (n = 43), MDVH for asymptomatic patients was compared with MDVH for patients experiencing both radiological and clinical pulmonary side-effects.
  
  
  RESULTS
  Moderate pulmonary complications, that is requiring treatment with corticosteroids, were rare following local RT (< 1%), but were diagnosed among 11% of the patients treated with LR-RT. A correlation between increasing irradiated lung volumes at the >20 Gy-level (V20), based on MDVH for the RT-techniques, and pulmonary complications was found (P < 0.001). Furthermore, increasing age and reduced pre-RT functional level were independently associated with a higher rate of pulmonary complications (P = 0.005 and P = 0.018). Among the subgroup of mastectomized patients treated with LR-RT, who had undergone complete 3-D dose planning, a difference in mean V20 was found between patients experiencing both clinical and radiological pulmonary side-effects compared to patients experiencing neither of the two side-effects (P = 0.007).
  
  
  CONCLUSIONS
  Moderate pulmonary complications following local RT for BC are rare. The incidence of short-term moderate pulmonary complications in LR-RT is, however, clinically significant and to define quality assurance guidelines for these RT-techniques, 3-D RT planning can be used.
authors.affiliation: Department of Radiotherapy, Huddinge University Hospital, Stockholm, Sweden. Pehr.Lind@abc.se
authors.forename: P A
authors.initials: PA
authors.lastname: Lind
authors.forename: B
authors.initials: B
authors.lastname: Wennberg
authors.forename: G
authors.initials: G
authors.lastname: Gagliardi
authors.forename: T
authors.initials: T
authors.lastname: Fornander
mesh_terms: D001943:Breast Neoplasms / Q000532:radiotherapy* / Q000601:surgery; D003131:Combined Modality Therapy; D005260:Female; D006801:Humans; D008168:Lung / Q000033:anatomy & histology* / Q000528:radiation effects; D008171:Lung Diseases / Q000453:epidemiology* / Q000209:etiology / Q000473:pathology / Q000517:prevention & control; D008408:Mastectomy; D008875:Middle Aged; D017410:Practice Guidelines as Topic; D011446:Prospective Studies; D011785:Quality Assurance, Health Care; D011829:Radiation Dosage; D011832:Radiation Injuries / Q000453:epidemiology* / Q000209:etiology / Q000473:pathology / Q000517:prevention & control; D011880:Radiotherapy Planning, Computer-Assisted / Q000592:standards; D018714:Radiotherapy, Adjuvant / Q000009:adverse effects* / Q000379:methods; D013548:Sweden / Q000453:epidemiology