Impact of radiation-induced xerostomia on quality of life after primary radiotherapy among patients with head and neck cancer.

Abstract

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. 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. 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. 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.