title: Late dysphagia after IMRT for head and neck cancer and correlation with dose-volume parameters.
abstract: OBJECTIVE
  Many head and neck cancer (HNC) survivors experience diminished quality of life due to radiation-induced dysphagia. The aim of this study was to investigate frequency, intensity and dose-volume dependency for late dysphagia in HNC patients treated with curative IMRT.
  
  
  METHODS
  Candidates for the study were 294 patients treated with primary IMRT from 2006 to 2010; a total of 259 patients accepted to participate by answering the EORTC QLQ-C30 and H&N35 questionnaires. A total of 65 patients were further examined with modified barium swallow (MBS) and saliva collection. Data on patient, tumor and treatment characteristics were prospectively recorded in the DAHANCA database. Dose-volume histograms (DVH) of swallowing-related structures were retrospectively analyzed.
  
  
  RESULTS
  QoL data showed low degree of dysphagia (QoL subscales scores of 17 and below) compared to objective measures. The most frequent swallowing dysfunction was retention; penetration and aspiration was less common. In general, objective measurements and observer-assessed late dysphagia correlated with dose to pharyngeal constrictor muscles (PCM), whereas QoL endpoints correlated with DVH parameters in the glottis/supraglottic larynx. Both xerostomia and dysphagia has been reduced after introduction of IMRT.
  
  
  CONCLUSIONS
  Radiation-induced dysphagia is still important, with a high degree of retention and penetration. Introduction of parotid-sparing IMRT has reduced the severity of dysphagia, primarily through a major reduction in xerostomia. Dose-response relationships were found for specific dysphagia endpoints.
authors.affiliation: Department of Oncology, Aarhus University Hospital, Denmark. hanna@oncology.dk
authors.forename: Hanna R
authors.initials: HR
authors.lastname: Mortensen
authors.forename: Kenneth
authors.initials: K
authors.lastname: Jensen
authors.forename: Karin
authors.initials: K
authors.lastname: Aksglæde
authors.forename: Marie
authors.initials: M
authors.lastname: Behrens
authors.forename: Cai
authors.initials: C
authors.lastname: Grau
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003430:Cross-Sectional Studies; D003679:Deglutition / Q000528:radiation effects; D003680:Deglutition Disorders / Q000209:etiology*; D005260:Female; D006258:Head and Neck Neoplasms / Q000523:psychology / Q000532:radiotherapy*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010609:Pharyngeal Muscles / Q000528:radiation effects; D011788:Quality of Life; D011832:Radiation Injuries; D011879:Radiotherapy Dosage; D050397:Radiotherapy, Intensity-Modulated / Q000009:adverse effects*
keywords: Dose–volume parameters; Head and neck cancer; Morbidity; Radiotherapy; Swallowing