title: Impact of radiation-induced xerostomia on quality of life after primary radiotherapy among patients with head and neck cancer.
abstract: OBJECTIVE
  To investigate the impact of xerostomia on overall quality of life (QoL) outcome and related dimensions among head and neck cancer patients treated with primary radiotherapy.
  
  
  METHODS
  A total of 288 patients with Stage I-IV disease without distant metastases were included. Late xerostomia according to the Radiation Therapy Oncology Group (RTOG-xerostomia) and QoL (European Organization for Research and Treatment of Cancer QLC-C30) were assessed at baseline and every 6th month from 6 months to 24 months after radiotherapy.
  
  
  RESULTS
  A significant association was found between RTOG-xerostomia and overall QoL outcome (effect size [ES] 0.07, p < 0.001). A significant relationship with global QoL, all functioning scales, and fatigue and insomnia was observed. A significant interaction term was present between RTOG-xerostomia and gender and between RTOG-xerostomia and age. In terms of gender, RTOG-xerostomia had a larger impact on overall QoL outcome in women (ES 0.13 for women vs. 0.07 for men). Furthermore, in women ES on individual scales were larger, and a marked worsening was observed with increasing RTOG-xerostomia. No different ES according to age was seen (ES 0.10 for 18-65 years vs. 0.08 for >65 years). An analysis of the impact of RTOG-xerostomia on overall QoL outcome over time showed an increase from 0.09 at 6 months to 0.22 at 24 months. With elapsing time, a worsening was found for these individual scales with increasing RTOG-xerostomia.
  
  
  CONCLUSIONS
  The results of this prospective study are the first to show a significant impact of radiation-induced xerostomia on QoL. Although the incidence of Grade > or =2 RTOG-xerostomia decreases with time, its impact on QoL increases. This finding emphasizes the importance of prevention of xerostomia.
authors.affiliation: Department of Radiation Oncology, University Medical Center, Utrecht, The Netherlands. a.p.jellema@umcutrecht.nl
authors.forename: Anke Petra
authors.initials: AP
authors.lastname: Jellema
authors.forename: Ben J
authors.initials: BJ
authors.lastname: Slotman
authors.forename: Patricia
authors.initials: P
authors.lastname: Doornaert
authors.forename: C René
authors.initials: CR
authors.lastname: Leemans
authors.forename: Johannes A
authors.initials: JA
authors.lastname: Langendijk
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D015986:Confounding Factors, Epidemiologic; D005221:Fatigue / Q000150:complications; D005260:Female; D006258:Head and Neck Neoplasms / Q000532:radiotherapy*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011788:Quality of Life; D012737:Sex Factors; D007319:Sleep Initiation and Maintenance Disorders / Q000150:complications; D013997:Time Factors; D014987:Xerostomia / Q000150:complications*