title: Changes in local pulmonary injury up to 48 months after irradiation for lymphoma and breast cancer.
abstract: OBJECTIVE
  To assess the recovery from early local pulmonary injury after irradiation and to determine whether regional differences exist.
  
  
  METHODS
  For 110 patients treated for breast cancer or malignant lymphoma, single photon emission computed tomography (SPECT) perfusion and ventilation scans and CT scans were made before, 3, 18, and 48 months after radiotherapy. Dose-effect relations for changes in local perfusion, ventilation, and density were determined for each individual patient using spatially correlated SPECT and CT data sets, for each follow-up period. Average dose-effect relations for both subgroups were determined, as well as dose-effect relations for different regions.
  
  
  RESULTS
  In general, partial improvement of local pulmonary injury was observed between 3 and 18 months for each of the three endpoints. After 18 months, no further improvement was seen. Patients with breast cancer and malignant lymphoma showed a similar improvement (except for the perfusion parameter), which was attributed to a recovery from the early radiation response and could not be explained by contraction effects of fibrosis of lung parenchyma. No regional differences in radiosensitivity 18 months after treatment were observed, except for the dorsal versus ventral region. This difference was attributed to a gravity-related effect in the measuring procedure.
  
  
  CONCLUSIONS
  For all patients, a partial recovery from early local perfusion, ventilation, and density changes, was seen between 3 and 18 months after radiotherapy. After 18 months, local lung function did not further improve (lymphoma patients).
authors.affiliation: Departments of Radiotherapy, The Netherlands Cancer Institute, Amsterdam.
authors.forename: J C
authors.initials: JC
authors.lastname: Theuws
authors.forename: Y
authors.initials: Y
authors.lastname: Seppenwoolde
authors.forename: S L
authors.initials: SL
authors.lastname: Kwa
authors.forename: L J
authors.initials: LJ
authors.lastname: Boersma
authors.forename: E M
authors.initials: EM
authors.lastname: Damen
authors.forename: P
authors.initials: P
authors.lastname: Baas
authors.forename: S H
authors.initials: SH
authors.lastname: Muller
authors.forename: J V
authors.initials: JV
authors.lastname: Lebesque
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001943:Breast Neoplasms / Q000503:physiopathology / Q000532:radiotherapy*; D004307:Dose-Response Relationship, Radiation; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008168:Lung / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000528:radiation effects*; D008223:Lymphoma / Q000503:physiopathology / Q000532:radiotherapy*; D008297:Male; D008875:Middle Aged; D011832:Radiation Injuries / Q000503:physiopathology*; D020127:Recovery of Function; D013997:Time Factors; D014057:Tomography, X-Ray Computed