title: Dose-volume-related dysphagia after constrictor muscles definition in head and neck cancer intensity-modulated radiation treatment.
abstract: OBJECTIVE
  Dysphagia remains a side effect influencing the quality of life of patients with head and neck cancer (HNC) after radiotherapy. We evaluated the relationship between planned dose involvement and acute and late dysphagia in patients with HNC treated with intensity-modulated radiation therapy (IMRT), after a recontouring of constrictor muscles (PCs) and the cricopharyngeal muscle (CM).
  
  
  METHODS
  Between December 2011 and December 2013, 56 patients with histologically proven HNC were treated with IMRT or volumetric-modulated arc therapy. The PCs and CM were recontoured. Correlations between acute and late toxicity and dosimetric parameters were evaluated. End points were analysed using univariate logistic regression.
  
  
  RESULTS
  An increasing risk to develop acute dysphagia was observed when constraints to the middle PCs were not respected [mean dose (Dmean) ≥50 Gy, maximum dose (Dmax) >60 Gy, V50 >70% with a p = 0.05]. The superior PC was not correlated with acute toxicity but only with late dysphagia. The inferior PC was not correlated with dysphagia; for the CM only, Dmax >60 Gy was correlated with acute dysphagia ≥ grade 2.
  
  
  CONCLUSIONS
  According to our analysis, the superior PC has a major role, being correlated with dysphagia at 3 and 6 months after treatments; the middle PC maintains this correlation only at 3 months from the beginning of radiotherapy, but it does not have influence on late dysphagia. The inferior PC and CM have a minimum impact on swallowing symptoms.
  
  
  CONCLUSIONS
  We used recent guidelines to define dose constraints of the PCs and CM. Two results emerge in the present analysis: the superior PC influences late dysphagia, while the middle PC influences acute dysphagia.
authors.affiliation: 1 Radiation Oncology, Sacro Cuore-Don Calabria Hospital, Negrar-Verona, Italy.
authors.forename: R
authors.initials: R
authors.lastname: Mazzola
authors.forename: F
authors.initials: F
authors.lastname: Ricchetti
authors.forename: A
authors.initials: A
authors.lastname: Fiorentino
authors.forename: S
authors.initials: S
authors.lastname: Fersino
authors.forename: N
authors.initials: N
authors.lastname: Giaj Levra
authors.forename: S
authors.initials: S
authors.lastname: Naccarato
authors.forename: G
authors.initials: G
authors.lastname: Sicignano
authors.forename: S
authors.initials: S
authors.lastname: Albanese
authors.forename: G
authors.initials: G
authors.lastname: Di Paola
authors.forename: D
authors.initials: D
authors.lastname: Alterio
authors.forename: R
authors.initials: R
authors.lastname: Ruggieri
authors.forename: F
authors.initials: F
authors.lastname: Alongi
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D003679:Deglutition / Q000528:radiation effects*; D003680:Deglutition Disorders / Q000000981:diagnostic imaging / Q000209:etiology* / Q000503:physiopathology; D005260:Female; D005500:Follow-Up Studies; D006258:Head and Neck Neoplasms / Q000532:radiotherapy*; D006801:Humans; D007821:Laryngeal Muscles / Q000503:physiopathology / Q000528:radiation effects*; D008297:Male; D008875:Middle Aged; D011788:Quality of Life; D011879:Radiotherapy Dosage; D050397:Radiotherapy, Intensity-Modulated / Q000009:adverse effects* / Q000379:methods; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed; D055815:Young Adult