ESTRO 2024 - Abstract Book

S1184

Clinical - Head & neck

ESTRO 2024

Using real-world data to validate a proposed ASD model developed on clinical trial data was unable to reliably and consistently predict patients who had suffered from the complication. It is likely that the model requires updating and expanding to take into consideration the evolution of head and neck cancer and the associated management since it was created.

Keywords: prediction model, dysphagia, toxicity

References:

1. Sharabiani M, Clementel E, Andratschke N, Hurkmans C. Generalizability assessment of head and neck cancer NTCP models based on the TRIPOD criteria. Radiotherapy and Oncology. 2020 May 1;146:143-50.

2. Dean JA, Wong KH, Gay H, Welsh LC, Jones AB, Schick U, Oh JH, Apte A, Newbold KL, Bhide SA, Harrington KJ. Functional data analysis applied to modeling of severe acute mucositis and dysphagia resulting from head and neck radiation therapy. International Journal of Radiation Oncology* Biology* Physics. 2016 Nov 15;96(4):820-31.

3.https://ctep.cancer.gov/protocoldevelopment/electronic_applications/docs/ctcae_v5_quick_reference_5x7.pdf

297

Proffered Paper

Radiation-induced xerostomia is related to stem cell dose-dependent reduction of saliva production

Maria I. van Rijn - Dekker 1 , Sacha la Bastide - van Gemert 2 , Monique A. Stokman 1 , Arjan Vissink 3 , Robert P. Coppes 1,4 , Johannes A. Langendijk 1 , Peter van Luijk 1 , Roel J.H.M. Steenbakkers 1 1 University Medical Centre Groningen, Department of Radiation Oncology, Groningen, Netherlands. 2 University Medical Centre Groningen, Department of Epidemiology, Groningen, Netherlands. 3 University Medical Centre Groningen, Department of Oral and Maxillofacial Surgery, Groningen, Netherlands. 4 University Medical Centre Groningen, Department of Biomedical Sciences of Cell and Systems, Groningen, Netherlands

Purpose/Objective:

Despite the use of advanced radiation techniques, patients with head and neck cancer (HNC) still experience xerostomia due to radiation-induced salivary gland damage. Previous studies showed that mean dose to the parotid gland Stem Cell Rich regions (D mean,SCR ) is the strongest predictor for the risk of patient-reported daytime xerostomia. However, the reason why D mean,SCR results in more xerostomia, is not yet elucidated. Therefore, this study tested the hypothesis that the relation between daytime xerostomia and D mean,SCR is explained by reduced saliva production related to dose to stem cells.

Material/Methods: