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Updated: May 17, 2026
Retroductal Submandibular Gland Instillation and Localized Fractionated Irradiation in a Rat Model of Salivary Hypofunction
Published on: April 24, 2016
Longitudinal Swallowing and Salivary Changes With CLR 131 and Re-Irradiation in Recurrent Head and Neck Cancer
Jenni Wu1,2,3,4, Sara Gustafson1,2,3,4, Meredith Hyun5
1Department of Communication Sciences and Disorders, University of Wisconsin-Madison, Madison, Wisconsin, USA.
Background:
Patients with recurrent head and neck cancer (HNC) often present with severe, persistent dysphagia and xerostomia following prior chemoradiation. Although swallowing impairments and salivary dysfunction have been reported in this population, prior longitudinal studies have not examined changes in salivary composition or how these changes relate to swallowing physiology.
Purpose:
This study characterized longitudinal changes in swallowing and salivary function-including composition-following treatment with CLR 131, a novel tumor-selective radiotherapeutic, combined with external beam radiation therapy (EBRT).
Methods:
Twelve patients with locoregionally recurrent HNC demonstrating CLR 131 uptake on SPECT/CT imaging were enrolled. Videofluoroscopic swallowing (VFS) studies and stimulated saliva collections were performed at baseline, 3, 6, and 12 months posttreatment. Outcomes included Dynamic Imaging Grade of Swallowing Toxicity (DIGEST) scores, swallowing temporal measures, patient-reported dysphagia using Eating Assessment Tool (EAT-10), and salivary flow rate, pH, and extensional viscosity.
Results:
At baseline, participants demonstrated significantly worse swallowing and salivary function than published normative data (p < 0.001). Most swallowing measures remained stable following treatment; however, time to laryngeal vestibule closure with 5 mL pudding was prolonged at 3 months (p < 0.02). Stimulated salivary flow rate declined significantly at 12 months (p < 0.001), while pH decreased at 3 months (p < 0.05) and extensional viscosity increased at 6 months (p < 0.02). From baseline to 3 months, EAT-10 scores were strongly associated with salivary pH and viscosity changes (r = 0.84 and -0.99, respectively). No swallowing timing measures predicted DIGEST safety or efficiency grades.
Conclusions:
These findings suggest that CLR 131 + EBRT did not exacerbate objective swallowing impairment in the early post-treatment period, but patient-reported dysphagia was sensitive to post-treatment salivary alterations. Integrating salivary assessments with instrumental and patient-reported outcomes may enhance detection of functional toxicity and guide targeted dysphagia management in recurrent HNC.
