title: Radiation-induced lung injury: a hypersensitivity pneumonitis?
abstract: Radiation pneumonitis occurs 6 to 12 weeks after thoracic irradiation, and is thought to be due to direct radiation-induced lung injury. Four patients who developed pneumonitis after unilateral thoracic irradiation for carcinoma of the breast were studied with bronchoalveolar lavage, gallium scan of the lung, and respiratory function tests. On the irradiated side of the chest, all four patients showed an increase in total cells recovered from the lavage fluid and a marked increase in the percentage of lymphocytes. When results for the unirradiated lung were compared with results for the irradiated lung, there was a comparable increase in total cells and percentage of lymphocytes. Gallium scans showed increases for both irradiated and unirradiated lungs. Prompt improvement was seen after corticosteroid therapy in all patients. The fact that abnormal findings occur equally in irradiated and unirradiated lung is inconsistent with simple direct radiation-induced injury and suggests an immunologically mediated mechanism such as a hypersensitivity pneumonitis.
authors.affiliation: St. Vincent's Hospital, Sydney, Australia.
authors.forename: P G
authors.initials: PG
authors.lastname: Gibson
authors.forename: D H
authors.initials: DH
authors.lastname: Bryant
authors.forename: G W
authors.initials: GW
authors.lastname: Morgan
authors.forename: M
authors.initials: M
authors.lastname: Yeates
authors.forename: V
authors.initials: V
authors.lastname: Fernandez
authors.forename: R
authors.initials: R
authors.lastname: Penny
authors.forename: S N
authors.initials: SN
authors.lastname: Breit
mesh_terms: D000368:Aged; D000542:Alveolitis, Extrinsic Allergic / Q000000981:diagnostic imaging / Q000209:etiology*; D001992:Bronchoalveolar Lavage Fluid / Q000166:cytology; D005260:Female; D005710:Gallium Radioisotopes; D006801:Humans; D008168:Lung / Q000000981:diagnostic imaging / Q000473:pathology / Q000528:radiation effects*; D008875:Middle Aged; D011832:Radiation Injuries / Q000000981:diagnostic imaging / Q000473:pathology*; D011877:Radionuclide Imaging
chemical_list: D005710:Gallium Radioisotopes