Post-Treatment Evaluation of Swallowing Function Using Quantitative Videofluoroscopy in Head and Neck Patients Undergoing Immunoradiotherapy or Chemoradiotherapy

Abstract

<h3>Purpose/Objective(s)</h3> To evaluate post-treatment swallowing function in head and neck squamous cell carcinoma (HNSCC) patients undergoing definitive chemoradiotherapy (CRT) vs. immunoradiotherapy (IRT) using quantitative videofluoroscopic swallow studies (qVFSS). <h3>Materials/Methods</h3> We conducted a cross-sectional study of 23 patients with previously untreated locoregionally advanced HNSCC using qVFSS 4-6 and/or 12-24 months after CRT or IRT. RT consisted of 70 Gy to the primary and 54-63 Gy to the neck in 35 fractions over 7 weeks. Systemic therapy consisted of concurrent cisplatin (N=14) or cetuximab (N=2) in the CRT group and concurrent + adjuvant pembrolizumab only in the IRT group. qVFSS studies were performed by a certified speech-language pathologist using C-arm fluoroscopy with standardized bolus protocol. Quantitative metrics (Pharyngeal Constriction Ratio (PCR), Total Pharyngeal Transit Time (TPT), Bolus Clearance Ratio (BCR), and Posterior Pharyngeal Wall Thickness (PPWT)) were calculated using Swallowtail® software (Belldev Medical LCC, Arlington Heights, IL), with raters blinded to treatment. Higher values of each metric indicate worse swallowing function. For patients undergoing multiple qVFSS, maximum values of each metric were used. Two sample <i>t</i> tests and Mann-Whitney U tests were used to compare metrics by treatment group. Paired <i>t</i> tests were used to compare pre vs. post-treatment qVFSS metrics. <h3>Results</h3> Two patients did not complete post-treatment qVFSS, leaving 21 for analysis (16 CRT, 5 IRT). Disease sites were: oropharynx-15, larynx-4, hypopharynx-1, unknown primary-1. Overall mean (SD) PCR, TPT, BCR, and PPWT were 0.15 (0.13), 0.96 (0.27), 14.4 (13.4), and 0.73 (0.24), respectively. Mean post-treatment PCR and BCR were significantly higher for patients receiving IRT vs. CRT (0.21 vs. 0.13, t test p<0.01 and 20.0 vs. 12.7, p=0.019, respectively) (<b>Table</b>). No significant differences were found in TPT or PPWT between groups (<b>Table</b>). Mean (SD) pre-treatment PCR, TPT, BCR, and PPWT were 0.18 (0.19), 0.91 (0.28), 11.6 (11.8), and 0.54 (0.16) respectively. No significant differences were observed comparing post- minus pre-treatment PCR (-0.042, p=0.36), TPT (+0.094, p=0.24), or BCR (+1.38, p=0.54); however, PPWT was significantly worse after treatment (+0.24, p=0.03). <h3>Conclusion</h3> Preliminary results indicate dysphagia is worse in patients treated with IRT; however, the analysis is limited by small sample and cross-sectional design. Future studies are needed to define effects of alternative treatments on dysphagia.