Risk Factors for Xerostomia following Radiotherapy of Head-and-Neck Cancers

Background/Aim: Many head-and-neck cancer patients receive radiotherapy, which may be associated with significant toxicities. Xerostomia is considered one of the most debilitating late adverse events. This study was performed to identify risk factors for xerostomia. Patients and Methods: Several characteristics were investigated for associations with late xerostomia in 159 patients irradiated for head-and-neck cancer including age, sex, tumor site and size, underlying pathology, histologic grading, upfront resection, systemic treatment, and type and dose of radiotherapy. Results: Ninety (57%) and 35 (22%) patients experienced grade ≥2 and ≥3 xerostomia, respectively. Grade ≥2 xerostomia was significantly associated with tumor site (nasopharynx/oropharynx/oral cavity/floor of mouth, p=0.049). Grade ≥3 xerostomia was significantly associated with age ≥61 years (p=0.035); trends were found for tumor site (p=0.088), bilateral nodal involvement (p=0.093), definitive treatment (p=0.082), and systemic treatment (p=0.055). Conclusion: Risk factors for xerostomia following radiotherapy of head-and-neck cancers were identified including older age, unfavorable tumor site, bilateral involvement of lymph nodes, definitive treatment, and addition of systemic therapies. For patients with risk factors, sparing of the salivary glands is particularly important.