title: Simulation study of high-dose-rate brachytherapy for early glottic cancer.
abstract: OBJECTIVE
  External beam radiation therapy (EBRT) is effective for early glottic cancers, with cure rates of ∼90% for T1 tumors. EBRT has strengths but also disadvantages including radiation to healthy tissues and duration of 5-7 weeks. With advances in laryngeal framework surgery, new devices can provide reliable, minimally invasive access to the larynx. Such devices could be modified to insert brachytherapy catheters. Brachytherapy could provide focused radiation while limiting dose to normal structures in the larynx and neck. As a preliminary step, we performed simulations comparing EBRT to high-dose-rate brachytherapy to assess if this approach could provide dosimetric advantage.
  
  
  METHODS
  One- and 2-catheter brachytherapy simulations were performed for 3 patients with T1 glottic carcinoma. Percentage of dose delivered to the target and adjacent structures was compared with conventional EBRT using 3D and intensity-modulated radiation therapy approaches.
  
  
  RESULTS
  Percentage of structures exposed to 50% of the dose was lower for brachytherapy compared with 3D EBRT and intensity-modulated radiation therapy, particularly for the cricoid and contralateral arytenoid. Dose was also lower for the carotid-internal jugular vein complexes compared with 3D EBRT. Dose profiles did not differ significantly between 1- and 2-catheter simulations.
  
  
  CONCLUSIONS
  Brachytherapy can decrease radiation to normal tissues including laryngeal cartilages and carotid-internal jugular vein complexes. Recent advancements allowing catheter placement may afford the potential to decrease radiation to healthy tissues with decreased treatment time. However, careful, stepwise evaluation of feasibility and outcomes in model systems is required before recommending this approach for such high cure rate cancers in humans.
authors.affiliation: Department of Surgery, Division of Otolaryngology-Head and Neck Surgery, University of Wisconsin-Madison School of Medicine and Public Health, Madison, WI.
authors.forename: Matthew R
authors.initials: MR
authors.lastname: Hoffman
authors.affiliation: Department of Surgery, Division of Otolaryngology-Head and Neck Surgery, University of Wisconsin-Madison School of Medicine and Public Health, Madison, WI. Electronic address: mccull@surgery.wisc.edu.
authors.forename: Timothy M
authors.initials: TM
authors.lastname: McCulloch
authors.affiliation: Department of Human Oncology, University of Wisconsin-Madison School of Medicine and Public Health, Madison, WI; Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, MD.
authors.forename: Pranshu
authors.initials: P
authors.lastname: Mohindra
authors.affiliation: Department of Human Oncology, University of Wisconsin-Madison School of Medicine and Public Health, Madison, WI.
authors.forename: Rupak
authors.initials: R
authors.lastname: Das
authors.affiliation: Department of Human Oncology, University of Wisconsin-Madison School of Medicine and Public Health, Madison, WI.
authors.forename: Mark
authors.initials: M
authors.lastname: Geurts
authors.affiliation: Department of Human Oncology, University of Wisconsin-Madison School of Medicine and Public Health, Madison, WI.
authors.forename: Paul M
authors.initials: PM
authors.lastname: Harari
mesh_terms: D000368:Aged; D001193:Arytenoid Cartilage / Q000528:radiation effects; D001918:Brachytherapy / Q000009:adverse effects* / Q000379:methods; D002277:Carcinoma / Q000532:radiotherapy*; D002343:Carotid Artery, Internal / Q000528:radiation effects; D057785:Catheters; D003198:Computer Simulation; D003413:Cricoid Cartilage / Q000528:radiation effects; D019583:Dose Fractionation, Radiation; D005931:Glottis; D006801:Humans; D007601:Jugular Veins / Q000528:radiation effects; D007822:Laryngeal Neoplasms / Q000532:radiotherapy*; D008297:Male; D008875:Middle Aged; D008954:Models, Biological; D011829:Radiation Dosage; D011832:Radiation Injuries / Q000209:etiology*; D050397:Radiotherapy, Intensity-Modulated / Q000009:adverse effects
keywords: Brachytherapy; External beam radiation therapy; Glottic carcinoma; Laryngeal framework surgery