ESTRO 2025 - Abstract Book

S1085

Clinical – Head & neck

ESTRO 2025

3522

Digital Poster ITHACA-ORION: Tools for Head and Neck Cancer – Early Post-Operative NI-RADS to Predict Recurrence in High-Risk Oral Cancer. Marangela Massaccesi 1 , Silvia Longo 1 , marco Panfili Panfili 2 , francesco Pastore 1 , calandrelli Rosalinda 2 , dario Mele 3 , alessandra Cassano 4 , Stefano Settimi 3 , francesco miccichè 5 , maria antonietta Gambacorta 1 1 UOC di Radioterapia Oncologica, Dipartimento Diagnostica per Immagini, Radioterapia Oncologica ed Ematologia,, Fondazione Policlinico Universitario Agostino Gemelli IRCCS,, rome, Italy. 2 Dipartimento Diagnostica per Immagini, Radioterapia Oncologica ed Ematologia,, Fondazione Policlinico Universitario Agostino Gemelli IRCCS,, rome, Italy. 3 Otorhinolaryngology Unit,, Fondazione Policlinico Universitario Agostino Gemelli IRCCS,, rome, Italy. 4 Dipartimento di scienze mediche e chirurgiche, Fondazione Policlinico Universitario Agostino Gemelli IRCCS,, rome, Italy. 5 U.O.C. di Radioterapia Oncologica,, Fatebenefratelli Isola Tiberina, Gemelli Isola, Rome, Italy Purpose/Objective: Oral cavity squamous cell carcinoma (SCC) in high-risk patients is often treated with surgery followed by post operative radiotherapy (PORT). However, early recurrence remains a significant concern. The Neck Imaging Reporting and Data System (NI-RADS) was developed to standardize post-treatment imaging and provide prognostic insights. This study evaluates the effectiveness of early NI-RADS categorization in predicting recurrence and survival in high-risk oral cavity SCC patients receiving PORT Material/Methods: This retrospective study included 84 high-risk oral cavity SCC patients who underwent radical surgery and were referred for PORT at the Fondazione Policlinico Universitario Agostino Gemelli IRCCS between January 2013 and May 2024. Post-operative contrast-enhanced CT or MRI was performed within 12 weeks, and NI-RADS scores were assigned to both primary tumor (T) and nodal (N) sites. Two independent neuroradiologists reviewed the scans, with progression-free survival (PFS) and overall survival (OS) analyzed according to early NI-RADS scores. Results: The median follow-up was 57 months. NI-RADS T and N scores were significantly associated with regional PFS and OS, with T categories predicting regional PFS (p=0.001) and OS (p=0.006), and N categories predicting regional PFS (p ≤ 0.0001) and OS (p=0.0008). Interobserver agreement was strong for both T (Weighted Kappa = 0.837) and N (Weighted Kappa = 0.855). Conclusion: Early NI-RADS scoring offers valuable prognostic information for high-risk oral cavity SCC patients, strongly correlating with recurrence and survival. Incorporating NI-RADS into early post-operative imaging may enhance treatment planning, identifying patients at higher risk of recurrence and enabling personalized care strategies.

Keywords: oral cancer, predictive tools, NI-RADS

3532

Digital Poster prospective clinical validation of a fully automated decision making system for adaptive radiotherapy in nasopharyngeal carcinoma Xiao-li Yu 1,2 , Jiang Hu 1 , Yu-xian Yang 1 , Guang-yu Wang 1 , Xin Yang 1 , Wen-chao Diao 1 , Lu Liu 1 , Xiao-bo Jiang 1 , Chen-di Xu 1 , Liu-wen Lin 1 , Le-cheng Jia 3 , Hua Li 3 , Yan-fei Liu 3 , Ying Sun 1 , Guan-qun Zhou 1 1 Radiation Oncology, Sun Yat-Sen University Cancer Center and State Key Laboratory of Oncology in Southern China, Collaborative Innovation Center of Cancer Medicine, Guangzhou, China. 2 Radiation Oncology, Sun Yat-sen