ESTRO 2025 - Abstract Book

S4348

RTT - Treatment planning, OAR and target definitions

ESTRO 2025

Conclusion:

Both softwares showed similar results overall, with each performing better in different anatomical areas. More than 30% of generated OARs require major editing or are not used, so there is still room for improvement in both softwares. Even though results were not at the desired level yet, we decided to implement one counting on expected software improvements. To complement this work, we will 1. Study the impact of the chosen software on RO contouring time and on the department workflow; 2. Compare automatically generated structures with those manually contoured.

Keywords: Artificial Intelligence, Autocontouring

2163

Poster Discussion VMAT versus 3D-CRT with continuous positive airway pressure in left-sided breast cancer irradiation: Are we comparing apples to oranges? Zeineb Naimi 1 , Amal Riahi 1 , Azza Slim 2 , Raouia Ben Amor 1 , Awatef Hamdoun 1 , Ghada Bouguerra 1 , Rihab Haddad 1 , Lotfi Kochbati 1 1 Radiation Oncology Department, Abderrahmen Mami Hospital, Ariana, Tunisia. 2 Pneumology Dpartment, Abderrahmen Mami Hospital, Ariana, Tunisia Purpose/Objective: This study aimed to compare OAR exposure in left-sided breast cancer radiotherapy using continuous positive airway pressure (CPAP) with either VMAT or 3D conformal RT. Material/Methods: Fifty patients referred for adjuvant left-sided breast cancer radiotherapy, between January and April 2024, were prospectively enrolled in this study. Patients underwent a planning CT with CPAP device, using a facial mask, after 30 minutes of breathing under a maximum tolerable pressure ≤15cmH2O. For each patient, 2 treatment plans were generated, using 3D conformal (3DCRT) and VMAT techniques. The prescription dose was 40.05Gy/15 fractions +/-