title: Reduction of the dose to the elective neck in head and neck squamous cell carcinoma, a randomized clinical trial using intensity modulated radiotherapy (IMRT). Dosimetrical analysis and effect on acute toxicity.
abstract: OBJECTIVE
  A randomized trial was initiated to investigate whether a reduction of the dose to the elective nodal sites and the swallowing apparatus delivered by IMRT would result in a reduction of acute and late side effects without compromising tumor control. The aim of this paper is to report on dosimetrical analysis and acute toxicity.
  
  
  METHODS
  Two-hundred patients were randomized. In the standard arm, elective nodal volumes (PTVelect) were irradiated up to an equivalent dose of 50Gy. In the experimental arm an equivalent dose of 40Gy was prescribed to the PTVelect. The dose to the swallowing apparatus was kept as low as possible without compromising therapeutic PTV (PTVther) coverage.
  
  
  RESULTS
  No significant difference was seen between both arms concerning PTVther coverage. The median D95 of the PTVelect was significantly lower in the experimental arm (39.5 vs 49.8Gy; p<0.001). Concerning the organs at risk, the dose to swallowing structures and spinal cord was significantly reduced. There was no significant difference in acute toxicity. Three months after radiotherapy there was significantly less grade ⩾3 dysphagia in the experimental arm (2% vs 11%; p=0.03). With a median follow-up of 6months no significant differences were observed in locoregional control, disease free survival or overall survival.
  
  
  CONCLUSIONS
  Using IMRT we were able to significantly reduce the dose to the PTVelect and several organs at risk without compromising PTVther coverage. This resulted in a significant reduction of severe dysphagia 3months after radiotherapy. Further follow-up is necessary to investigate whether these observations translate into a benefit on late treatment related dysphagia without affecting treatment outcome.
authors: Department of Experimental Radiotherapy KU Leuven, Campus Gasthuisberg, Belgium. Electronic address: sandra.nuyts@uzleuven.be.
authors: Sandra
authors: S
authors: Nuyts
authors: Maarten
authors: M
authors: Lambrecht
authors: Fréderic
authors: F
authors: Duprez
authors: Jean-Francois
authors: JF
authors: Daisne
authors: Dirk
authors: D
authors: Van Gestel
authors: Danielle
authors: D
authors: Van den Weyngaert
authors: Nele
authors: N
authors: Platteaux
authors: Yasmyne
authors: Y
authors: Geussens
authors: Mia
authors: M
authors: Voordeckers
authors: Indira
authors: I
authors: Madani
authors: Wilfried
authors: W
authors: De Neve
mesh_terms: D000328:Adult; D000368:Aged; D002294:Carcinoma, Squamous Cell / Q000532:radiotherapy*; D005260:Female; D006258:Head and Neck Neoplasms / Q000532:radiotherapy*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011879:Radiotherapy Dosage; D050397:Radiotherapy, Intensity-Modulated / Q000009:adverse effects*; D000077195:Squamous Cell Carcinoma of Head and Neck
keywords: Dose reduction; Elective nodes; Head and neck cancer; Radiotherapy