title: Positron emission tomography demonstrates radiation-induced changes to nonirradiated lungs in lung cancer patients treated with radiation and chemotherapy.
abstract: OBJECTIVE
  To determine whether acute changes in shielded lungs can be detected by positron emission tomography (PET) after radiation therapy.
  
  
  METHODS
  Retrospective cohort study.
  
  
  METHODS
  University-affiliated medical center.
  
  
  METHODS
  Sixteen patients undergoing radiation therapy for lung cancer who had PET scans after receiving treatment.
  
  
  METHODS
  None.
  
  
  RESULTS
  Thirteen of 16 patients (81.2%) showed increased (18)fluoro-2-deoxyglucose uptake in shielded nonirradiated lung in the following four distinct patterns: (1) contralateral peripheral pleural uptake in 5 of 16 patients (31.2%); (2) ipsilateral peripheral pleural uptake in 5 of 16 patients (31.2%); (3) bilateral peripheral pleural uptake in 1 of 16 patients (6.2%); and (4) bilateral diffuse background uptake in 1 of 16 patients (6.2%). This last patient developed clinically evident radiation pneumonitis.
  
  
  CONCLUSIONS
  Increased lung metabolic activity can be demonstrated in the nonirradiated lung in patients who have undergone radiation therapy for lung cancer and can be detected by PET scanning. PET scanning of lungs in irradiated patients may provide an early demonstrable barometer of pulmonary toxicity. If verified, this imaging tool could prove to be useful in monitoring patients receiving radiation therapy for thoracic malignancies and may have predictive value for subsequent fibrosis. PET scanning may also be an important tool in future studies to further elucidate the pathogenetic mechanism of radiation-induced lung injury.
authors.affiliation: Section of Pulmonary and Critical Care Medicine, Rush University Medical Center, Chicago, IL, USA. hesham74@qmail.com
authors.forename: Hesham A
authors.initials: HA
authors.lastname: Hassaballa
authors.forename: Elliot S
authors.initials: ES
authors.lastname: Cohen
authors.forename: Atif J
authors.initials: AJ
authors.lastname: Khan
authors.forename: Amjad
authors.initials: A
authors.lastname: Ali
authors.forename: Philip
authors.initials: P
authors.lastname: Bonomi
authors.forename: David B
authors.initials: DB
authors.lastname: Rubin
mesh_terms: D000971:Antineoplastic Combined Chemotherapy Protocols; D015331:Cohort Studies; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008168:Lung / Q000378:metabolism*; D008175:Lung Neoplasms / Q000188:drug therapy / Q000532:radiotherapy*; D049268:Positron-Emission Tomography; D011832:Radiation Injuries / Q000000981:diagnostic imaging* / Q000209:etiology / Q000378:metabolism; D017564:Radiation Pneumonitis / Q000000981:diagnostic imaging / Q000209:etiology / Q000378:metabolism; D011835:Radiation Protection; D019275:Radiopharmaceuticals; D012189:Retrospective Studies
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18