51 Dosimetric evaluation of dysphagia in early stage larynx cancer treated with definitive radiotherapy

• Published in: Radiotherapy and oncology 2024-03, Vol.192, p.S83-S86
• Main Authors: Babayigit, Yunus, Bascik, Oguzhan, Birgi, Sumerya Duru, Kar, İrem, Kurtman, Cengiz, Akyurek, Serap
• Format: Article
• Language: English
• Subjects: dysphagia; early stage larynx cancer; radiotherapy
• ISSN: 0167-8140; 1879-0887
• DOI: 10.1016/S0167-8140(24)00465-1

Current studies have identified the relationship between organs at risk (OAR) doses and swallowing functions in patients with head and neck cancer treated with radiotherapy (RT). Our aim is to evaluate the relationship between OAR doses and acute dysphagia in early stage larynx cancer patients received definitive RT and to examine the effect of the RT technique on OAR doses. Early-stage patients (Tcis-2N0M0) diagnosed between July 2014 and September 2022 were evaluated retrospectively. OAR (tongue base-TB, upper pharyngeal wall-UPW, middle pharyngeal wall-MPW, lower pharyngeal wall-LPW, whole pharyngeal wall-WPW, proximal esophagus-PE) were delineated subsequently and the dose-volume parameters were generated on previous treatment plans. Acute toxicities observed in the first 6 months were determined according to CTCAE v5. The relationship between OAR doses and grade(G) 2-3 dysphagia was investigated. For significant parameters (p 13.3cc, V55> 12.9cc, V60 >12.5cc; MPW V50> 3cc, V55> 3cc, V60> 2.7cc, V65>0.6cc and TB V65>0.05cc were determined as cut off values. Intensity-modulated radiotherapy (IMRT) technique and volumetric arc therapy (VMAT) technique were used in 25 (58%) and 17 (40%) patients, respectively. When the planning technique and the average dose-volume parameters in OARs were compared, WPW-Dmean, V50,V55, V60, V65; UPW- Dmean, V55, V60; LPW-Dmean, V65 and PE-Dmax had significantly decreased in VMAT plans. However, there was no clinically significant difference between the two techniques in terms of dysphagia (p = .41).