Global assessment of swallow function (GASF) following VMAT radiotherapy for head and neck squamous cell carcinoma

Abstract

Aim This study aimed to conduct a global assessment of swallow function (GASF) using a range of swallow outcome tools, in a cohort of patients pre- and post-treatment with image-guided volumetric modulated arc therapy (VMAT) radiotherapy.

Materials and methods All patients receiving radical (chemo)radiation for SCC of the larynx, oro-, hypo- or nasopharynx between October 2016 – 2021 were eligible for inclusion. Patients were treated with VMAT radiotherapy according to institutional and national protocols.

Patients underwent GASF pre- and 6 months post-treatment. Data were collated from the MD Anderson Dysphagia Inventory (MDADI), the Functional Oral Intake Scale (FOIS), the Performance Status Scale-Head and Neck: Normalcy of Diet scale (PSS-NoD), the 100 ml water swallow test (WST) for capacity and maximal interincisal opening (MIO).

Results One hundred and seventy-five patients were included. 55.2 % of patients experienced a fall in MDADI-Composite score greater than the published meaningful clinical important difference (MCID).A trend for a decrease in FOIS score reflects a decrease in range of diet textures and increase in reliance on enteral feeding at 6 months post-treatment. Mean PSS-NoD score decreased reflecting increased restriction in diet textures.20 patients’ WST capacity improved by the minimal clinically important difference of > 4mls whilst 37 % of patients experienced a decrease in WST capacity of 4mls or more. 12.6 % of patients developed trismus following radiotherapy.

Conclusions This paper adds new detail to the understanding of the decline in measured eating, drinking and swallowing function that patients treated with VMAT radiotherapy experience at 6 months post treatment. However, gaps are highlighted in the evidence base in terms of interpretation of swallow outcomes tool scores; future research in HNC should include ongoing discussion and development around robust outcomes tools and data collection.