title: Dysphagia and trismus after concomitant chemo-Intensity-Modulated Radiation Therapy (chemo-IMRT) in advanced head and neck cancer; dose-effect relationships for swallowing and mastication structures.
abstract: OBJECTIVE
  Prospective assessment of dysphagia and trismus in chemo-IMRT head and neck cancer patients in relation to dose-parameters of structures involved in swallowing and mastication.
  
  
  METHODS
  Assessment of 55 patients before, 10-weeks (N=49) and 1-year post-treatment (N=37). Calculation of dose-volume parameters for swallowing (inferior (IC), middle (MC), and superior constrictors (SC)), and mastication structures (e.g. masseter). Investigation of relationships between dose-parameters and endpoints for swallowing problems (videofluoroscopy-based laryngeal Penetration-Aspiration Scale (PAS), and study-specific structured questionnaire) and limited mouth-opening (measurements and questionnaire), taking into account baseline scores.
  
  
  RESULTS
  At 10-weeks, volume of IC receiving ≥60 Gy (V60) and mean dose IC were significant predictors for PAS. One-year post-treatment, reported problems with swallowing solids were significantly related to masseter dose-parameters (mean, V20, V40 and V60) and an inverse relationship (lower dose related to a higher probability) was observed for V60 of the IC. Dose-parameters of masseter and pterygoid muscles were significant predictors of trismus at 10-weeks (mean, V20, and V40). At 1-year, dose-parameters of all mastication structures were strong predictors for subjective mouth-opening problems (mean, max, V20, V40, and V60).
  
  
  CONCLUSIONS
  Dose-effect relationships exist for dysphagia and trismus. Therefore treatment plans should be optimized to avoid these side effects.
authors.affiliation: The Netherlands Cancer Institute, Department of Head and Neck Oncology & Surgery, Amsterdam, The Netherlands. l.vd.molen@nki.nl
authors.forename: Lisette
authors.initials: L
authors.lastname: van der Molen
authors.forename: Wilma D
authors.initials: WD
authors.lastname: Heemsbergen
authors.forename: Rianne
authors.initials: R
authors.lastname: de Jong
authors.forename: Maya A
authors.initials: MA
authors.lastname: van Rossum
authors.forename: Ludi E
authors.initials: LE
authors.lastname: Smeele
authors.forename: Coen R N
authors.initials: CR
authors.lastname: Rasch
authors.forename: Frans J M
authors.initials: FJ
authors.lastname: Hilgers
mesh_terms: D000328:Adult; D000368:Aged; D059248:Chemoradiotherapy / Q000009:adverse effects*; D003679:Deglutition / Q000187:drug effects / Q000528:radiation effects*; D003680:Deglutition Disorders / Q000209:etiology*; D004307:Dose-Response Relationship, Radiation; D005260:Female; D006801:Humans; D008297:Male; D008409:Mastication / Q000187:drug effects / Q000528:radiation effects*; D008875:Middle Aged; D050397:Radiotherapy, Intensity-Modulated / Q000009:adverse effects*; D011795:Surveys and Questionnaires; D014313:Trismus / Q000209:etiology*