title: Non-invasive objective evaluation of radiotherapy-induced dry mouth.
abstract: BACKGROUND
  Dry mouth is a common complaint in patients undergoing radiotherapy. Here, we employed the oral moisture meter Mucus III to evaluate dry mouth in head and neck tumor patients before and after they underwent radiotherapy.
  
  
  METHODS
  We recruited 17 newly diagnosed patients with pharyngeal squamous cell carcinoma or unknown primary squamous cell carcinoma, who received head and neck radiation therapy at Tokyo University Hospital in 2008-2010. The primary sites were the epipharynx (n = 1), oropharynx (n = 6), or hypopharynx (n = 5); it was unknown in five cases. Salivary function was assessed by a dry mouth questionnaire, resting saliva test, chewing gum test, and Mucus III, before (n = 17), immediately after radiotherapy (n = 10), and at 3 (n = 9) and 12 months after radiotherapy (n = 11).
  
  
  RESULTS
  The questionnaire, resting saliva test, and chewing gum test at 3 and 12 months after radiotherapy indicated a significantly decreased resting and stimulated whole saliva flow rate than prior radiotherapy (P < 0.05 and P < 0.001). In contrast, Mucus III results showed significant worsening of xerostomia at 12 months after radiotherapy (P < 0.05).
  
  
  CONCLUSIONS
  Mucus III has been proven to be an objective diagnostic tool for patients with serious dry mouth, such as in patients with Sjogren's syndrome. However, we did not find a perfect correlation between Mucus III and other objective (resting saliva and chewing gum) and subjective (questionnaire) measures of dry mouth. To precisely diagnose radiotherapy-induced dry mouth, further improvement to the method is needed.
authors.affiliation: Department of Otolaryngology, Faculty of Medicine, Graduate School of Medicine, University of Tokyo, Tokyo, Japan; Department of Artificial Organs and Otolaryngology, National Institute of Sensory Organs, Tokyo, Japan.
authors.forename: Youko
authors.initials: Y
authors.lastname: Fujimaki
authors.forename: Koichi
authors.initials: K
authors.lastname: Tsunoda
authors.forename: Shin-Ichi
authors.initials: S
authors.lastname: Ishimoto
authors.forename: Kazunari
authors.initials: K
authors.lastname: Okada
authors.forename: Makoto
authors.initials: M
authors.lastname: Kinoshita
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Igaki
authors.forename: Atsuro
authors.initials: A
authors.lastname: Terahara
authors.forename: Takahiro
authors.initials: T
authors.lastname: Asakage
authors.forename: Tastuya
authors.initials: T
authors.lastname: Yamasoba
mesh_terms: D000328:Adult; D000368:Aged; D002294:Carcinoma, Squamous Cell / Q000532:radiotherapy; D017024:Chemotherapy, Adjuvant; D002638:Chewing Gum; D017097:Electric Impedance; D004568:Electrodiagnosis / Q000295:instrumentation; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007012:Hypopharyngeal Neoplasms / Q000532:radiotherapy; D008297:Male; D008875:Middle Aged; D009061:Mouth Mucosa / Q000503:physiopathology; D009382:Neoplasms, Unknown Primary / Q000532:radiotherapy; D009959:Oropharyngeal Neoplasms / Q000532:radiotherapy; D010610:Pharyngeal Neoplasms / Q000532:radiotherapy*; D011879:Radiotherapy Dosage; D012463:Saliva / Q000378:metabolism; D057566:Self Report; D011795:Surveys and Questionnaires; D014987:Xerostomia / Q000175:diagnosis*
chemical_list: D002638:Chewing Gum
keywords: head and neck cancer; xerostomia