title: [Irradiation of hepatocellular carcinoma: impact of breathing on motions and variations of volume of the tumor, liver and upper abdominal organs].
abstract: OBJECTIVE
  To evaluate the amplitude of motion and the variations of volume of the tumor, the liver and upper abdominal organs induced by breathing during the irradiation of hepatocellular carcinoma (HCC).
  
  
  METHODS
  Two scanners were performed in inhale and in exhale not forced in 20 patients with a HCC. The liver (left/right lobes), the tumor, the duodenum, the two kidneys and the pancreas were delineated on each acquisition. The superposition of the two spirals made it possible to measure the displacements and variations of volume of these structures in the craniocaudal (CC), lateral (Lat), and anteroposterior (AP) directions.
  
  
  RESULTS
  The mean displacement of the tumour in CC, Lat and AP was of 19.7+/-8.3 mm, 4.5+/-2.3 mm, and 8.9+/-6.5 mm. The greatest amplitude of movement was obtained in CC for the right and left hepatic lobes (19+/-6.5 mm, 10+/-5.6 mm), the duodenum(12.6+/-6.4 mm), the kidneys right and left (15.5+/-6.1 mm, 16.2+/-10 mm) and the pancreas (13.2+/-6 mm). No significant variation of volume was observed for these organs.
  
  
  CONCLUSIONS
  The movements of the tumour, the liver and the abdominal organs, induced by breathing are significant. The respiratory gating appears essential in particular with the development of new techniques of irradiation such as the intensity-modulated radiotherapy (IMRT) or the stereotactic body radiation therapy (SBRT).
authors.affiliation: Service de radiothérapie-oncologie Rhône-Alpes, centre hospitalier Lyon-Sud, 165, chemin du Grand-Revoyet, 69495 Pierre-Bénite cedex, France.
authors.forename: A
authors.initials: A
authors.lastname: Kubas
authors.forename: F
authors.initials: F
authors.lastname: Mornex
authors.forename: P
authors.initials: P
authors.lastname: Merle
authors.forename: A
authors.initials: A
authors.lastname: d'Hombres
authors.forename: F
authors.initials: F
authors.lastname: Lorchel
authors.forename: O
authors.initials: O
authors.lastname: Chapet
mesh_terms: D006528:Carcinoma, Hepatocellular / Q000473:pathology / Q000503:physiopathology / Q000532:radiotherapy*; D045853:Exhalation / Q000502:physiology; D006801:Humans; D001239:Inhalation / Q000502:physiology; D008099:Liver / Q000033:anatomy & histology / Q000502:physiology / Q000503:physiopathology / Q000528:radiation effects; D008113:Liver Neoplasms / Q000473:pathology / Q000503:physiopathology / Q000532:radiotherapy*; D009043:Motor Activity; D015656:Respiratory Mechanics