title: Voice outcomes for photoangiolytic KTP laser treatment of early glottic cancer.
abstract: OBJECTIVE
  Surgery and radiotherapy routinely provide high cure rates in treating early glottic cancer. Therefore, key metrics for success are optimal voice outcome and preservation of future cancer treatment options. Remarkably, there is a paucity of pretreatment versus posttreatment voice outcome data. Angiolytic KTP (potassium titanyl phosphate) laser treatment of early glottic cancer with ultranarrow margins was initiated to better preserve vocal function. Given that effective oncological results have been achieved, it was hypothesized that this approach would also result in improved posttreatment measures of vocal function that more closely approximate historical norms than pretreatment values.
  
  
  METHODS
  Pretreatment and posttreatment voice outcome data were obtained for 92 patients (64 with T1 cancer and 28 with T2 cancer) who underwent 532-nm KTP laser treatment of early glottic cancer in a study design in which each patient essentially served as his or her own control. The evaluations included objective measures (acoustic and aerodynamic) and patients' self-assessments of vocal function (Voice-Related Quality of Life; V-RQOL). A series of mixed analyses of variance were conducted for all vocal function measures, with tumor stage and depth of invasion as the between-subjects variables and time (presurgery versus postsurgery) as the within-subject variable.
  
  
  RESULTS
  There were statistically significant (p < or = 0.05) postoperative improvements for acoustic (perturbation and noise-to-harmonics ratio) and aerodynamic (subglottic pressure and vocal efficiency) measures of vocal function, as well as for V-RQOL assessment.
  
  
  CONCLUSIONS
  Comprehensive pretreatment and posttreatment voice measures in a large patient cohort demonstrated that the KTP laser significantly improved postoperative vocal function in patients with early glottic cancer. Furthermore, radiotherapy was preserved as an oncological treatment option.
authors.affiliation: Department of Surgery, Harvard Medical School, Massachusetts General Hospital, Boston, Massachusetts, USA.
authors.forename: Aaron D
authors.initials: AD
authors.lastname: Friedman
authors.forename: Robert E
authors.initials: RE
authors.lastname: Hillman
authors.forename: Tali
authors.initials: T
authors.lastname: Landau-Zemer
authors.forename: James A
authors.initials: JA
authors.lastname: Burns
authors.forename: Steven M
authors.initials: SM
authors.lastname: Zeitels
mesh_terms: D000162:Acoustics; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002294:Carcinoma, Squamous Cell / Q000473:pathology / Q000601:surgery*; D005260:Female; D005931:Glottis / Q000601:surgery*; D006258:Head and Neck Neoplasms / Q000473:pathology / Q000601:surgery*; D006801:Humans; D007822:Laryngeal Neoplasms / Q000473:pathology / Q000601:surgery*; D007828:Laryngoscopy / Q000009:adverse effects / Q000379:methods*; D053844:Lasers, Solid-State / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D011788:Quality of Life; D012189:Retrospective Studies; D000077195:Squamous Cell Carcinoma of Head and Neck; D016896:Treatment Outcome; D014831:Voice; D014832:Voice Disorders / Q000209:etiology; D014833:Voice Quality; D055815:Young Adult