ESTRO 2025 - Abstract Book

S1403

Clinical - Lung

ESTRO 2025

Average esophageal DSMs per grade of acute esophagitis are presented in Figure 1. Figure 2 displays the average proportion of circumference irradiated to minimum 30 Gy versus the corresponding length of the esophagus. Patients with grade 2 and 3 esophagitis generally received a larger part of the esophageal circumference irradiated at longer lengths. Patients with grade 3 esophagitis in the standard-dose and high-dose arms received similar mean esophageal doses, with median values in each group of 24.0 and 23.6 Gy respectively. This was likely because the same mean dose constraint was applied to both groups. Consequently, the doses to the esophagus were delivered differently, with a higher maximum dose delivered to a smaller region in the high-dose arm, and larger regions irradiated at lower doses in the standard-dose arm. Conclusion: Both irradiated circumference and length seem important for acute esophagitis. Identifying a single dose limit is difficult; higher doses appear to be tolerated if the irradiated area is limited, but larger regions irradiated to intermediate doses should also be avoided to reduce toxicity. The 1 week longer treatment time for the high-dose arm might have been beneficial considering the similar mean doses.

Keywords: small cell lung cancer, esophagitis, radiotherapy

3633

Digital Poster Hypofractionated radiochemotherapy in non-small cell lung cancer in a real-world setting. A single-center experience. Irene Fajardo Paneque 1,2 , Sarah Sayago Gil 1,2 , Raquel Rodriguez Sánchez 1,2 , Ricardo Andrés Oyarzun Silva 3 , María del Carmen Herrera del Valle 3 , Javier Jaén Olasolo 3,2,1 1 RADIATION ONCOLOGY, HU JEREZ, JEREZ DE LA FRA., Spain. 2 INiBICA, HU JEREZ, JEREZ DE LA FRA., Spain. 3 RADIATION ONCOLOGY, HUPM, CÁDIZ, Spain Purpose/Objective: To analyse the tolerability and outcomes of hypofractionated radiotherapy for non-small cell lung cancer (NSCLC), with or without concomitant or prior chemotherapy, in a real-world setting from a single institution.