ESTRO 2025 - Abstract Book

S298

Brachytherapy – Head & neck, skin, eye

ESTRO 2025

2800

Proffered Paper Hybrid HDRIBT followed by IMRT (HyBIRT) technique for the definitive treatment of oral tongue SCC (OTSCC) – first in human prospective study Gokula Kumar Appalanaido 1 , Muhamad Yusri Musa 1 , Seng Ewe Ch’ng 1 , Syadwa Abdul Shukor 2 , Siti Noor Fazliah Mohd Noor 1 , Ahmad Fakrurrozi Mohamad 1 , Keerthaanaa Yogabalan 1 , Nor Hafizah Ishak 1 , Francis Hao 2 , Mohd Zahri Abdul Aziz 1 , Nursyatina Abdul Raof 1 , Reduan Abdullah 3 , Jasmin Jalil 1 1 Advanced Medical & Dental Institute, Universiti Sains Malaysia, Penang, Malaysia. 2 Department of Radiation Oncology, National University Cancer Institute, Singapore, Singapore. 3 Hospital Universiti Sains Malaysia, Universiti Sains Malaysia, Kelantan, Malaysia Purpose/Objective: The radiotherapy technique, rationale, initial clinical outcome and quality of life of 11 OTSCC patients who underwent definitive hybrid brachytherapy followed by IMRT (HyBIRT technique) was presented as proffered papers in the ESTRO 2023 and ESTRO 2024 (1, 2). Based on the promising initial results, this prospective study on the HyBIRT technique was initiated after receiving institutional human ethics board approval. Material/Methods: Thirty-one OTSCC patients who refused or unfit for surgery and were enrolled into this prospective study from January 2021 till April 2024 were analyzed. For statistical analysis, these patients were pooled together with the earlier cohort of 11 patients. The computerized treatment planning system generated IMRT plan of the HyBIRT technique with isodose lines is shown in figure 1A and patient/disease characteristic as in figure 1B. Prospectively enrolled patients were subjected to Pet-CT scan at 2 - 3 months for treatment response assessment.