title: Role of chest radiography in the diagnosis and follow-up of pulmonary metastasis in differentiated thyroid cancer.
abstract: BACKGROUND
  Post-treatment I-131 whole body scan (WBS) is known to be a very sensitive test in detecting metastasis in differentiated thyroid cancer (DTC). Therefore, in the presence of this sensitive method, the role of chest radiography (CXR) in the diagnosis of pulmonary metastasis has been questioned.
  
  
  OBJECTIVE
  The present study aimed to find the prevalence of pulmonary metastasis found on CXR in DTC patients who had negative post-treatment WBS.
  
  
  METHODS
  Retrospective comparison was undertaken of CXR and post-treatment WBS routinely performed in 300 DTC patients during the time of I-131 treatment from January 2003 to December 2006 in the Department of Radiology. Radiographic patterns of pulmonary metastasis classified as single nodule, multiple nodules, lymphangitic metastasis and pleural metastasis were also recorded.
  
  
  RESULTS
  Of the 300 DTC patients, 36 pulmonary metastases (12.0%) were diagnosed based on CXR and post-treatment I-131 WBS. Of these 36 cases, 11 (30.6%) were detected by both CXR and WBS, whereas 16 (44.4%) were detected by WBS alone and 9 (25.0%) by CXR alone. Seven of these 9 cases (77.8%) had lymphangitic pattern of pulmonary metastasis.
  
  
  CONCLUSIONS
  Although routine CXR has a limited role in the diagnosis of pulmonary metastasis in DTC patients being treated with I-131, it is helpful in detecting pulmonary metastasis in patients with negative post-treatment WBS.
authors.affiliation: Department of Radiology, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand. chasom@kku.ac.th
authors.forename: Charoonsak
authors.initials: C
authors.lastname: Somboonporn
authors.forename: Pannipa
authors.initials: P
authors.lastname: Simthamnimit
authors.forename: Warinthorn
authors.initials: W
authors.lastname: Puttharak
authors.forename: Panaya
authors.initials: P
authors.lastname: Tumsatan
authors.forename: Chetta
authors.initials: C
authors.lastname: Ngamjarus
authors.forename: Krisana
authors.initials: K
authors.lastname: Roysri
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007457:Iodine Radioisotopes / Q000008:administration & dosage*; D008168:Lung / Q000000981:diagnostic imaging*; D008175:Lung Neoplasms / Q000000981:diagnostic imaging* / Q000453:epidemiology / Q000556:secondary*; D008297:Male; D008875:Middle Aged; D009362:Neoplasm Metastasis / Q000000981:diagnostic imaging*; D015995:Prevalence; D012189:Retrospective Studies; D013785:Thailand / Q000453:epidemiology; D013954:Thyroglobulin / Q000097:blood; D013964:Thyroid Neoplasms / Q000453:epidemiology / Q000473:pathology* / Q000628:therapy; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome; D051598:Whole Body Imaging; D055815:Young Adult
chemical_list: D007457:Iodine Radioisotopes; D013954:Thyroglobulin