Dysphagia Aspiration Related Structures [DARS] Optimised Volumetric Modulated Arc Therapy in Head and Neck Cancers - Abstract
Background and purpose: There is a significant relationship between radiation dose to the pharyngeal constrictor muscles (PCM) and swallowing dysfunction during chemoradiotherapy of head and neck cancers. We aimed at sparing the pharyngeal constrictors using VMAT and assessing its impact on swallowing function.
Materials and methods: 28 patients with squamous cell carcinoma of oropharynx, hypopharynx, larynx and oral cavity, received a dose of 66Gy in 30 fractions. Doses to the constrictor muscles were
composite scores, at baseline and 3 months post radiotherapy. Objective assessments were done using Functional Endoscopic Evaluation of Swallowing (FEES).
Results: The Superior, Middle and inferior constrictor out received a mean dose of 43.5 Gy (SD 9.6), 48.6 Gy (SD 4.5) and 24.2 Gy (SD 11.1) respectively. We found a statistically significant between group difference of 14.2 + 6.1 in the mean MDADI composite scores between the two groups. 40% of the patients were grade 1on Murray`s secretion scale pre-treatment vs 15% at 3 months post treatment. During pre-treatment assessment by FEES, 14% of the patients were classified as penetrators and none were aspirators as per the Rosenbek’s Penetration-Aspiration scale vs 10.7% penetrators and no aspirators at 3 months post treatment.
Conclusion: DARS optimised radiotherapy with SIB-VMAT is feasible in patients with head and neck cancers and has potential to decrease the severity of dysphagia without compromising the overall treatment outcomes.