Xerostomia after radiotherapy

Abstract

Xerostomia is a debilitating side effect of radiotherapy in patients with head and neck cancer. We undertook a prospective study of the effect on xerostomia and outcomes of sparing one or both parotid glands during radiotherapy for patients with squamous cell carcinoma of the head and neck. Patients with locally advanced squamous cell carcinoma of the head and neck received definitive (70Gy in 2Gy fractions) or adjuvant (60-66Gy in 2Gy fractions) curative-intent radiotherapy using helical tomotherapy with concurrent chemotherapy if appropriate. GroupA received < 26Gy to the left and right parotids and groupB received < 26Gy to either parotid. The study included 126patients; 114 (55 in groupA and 59 in groupB) had follow-up data. There were no statistically significant differences between groups in disease stage. Xerostomia was significantly reduced in groupA vs. groupB (p = 0.0381). Patients in groupA also had significantly less dysphagia. Relapse-free and overall survival were not compromised in groupA: 2-year relapse-free survival was 86% vs. 72% in groupB (p = 0.361); 2-year overall survival was 88% and 76%, respectively (p = 0.251). This analysis suggests that reducing radiotherapy doses to both parotid glands to < 26Gy can reduce xerostomia and dysphagia significantly without compromising survival. Sparing both parotids while maintaining target volume coverage and clinical outcome should be the treatment goal and reporting radiotherapy doses delivered to the individual parotids should be standard practice.