ESTRO 2024 - Abstract Book

S4225

Physics - Intra-fraction motion management and real-time adaptive radiotherapy

ESTRO 2024

This work demonstrates that software-enabled real-time intrafraction motion monitoring improves treatment accuracy for prostate SABR. This work indicates the need for ongoing development and integration of real-time motion monitoring technologies with the standard radiotherapy equipment to improve treatment accuracy.

Keywords: Real-time IGRT, Prostate tumour motion

References:

1. Kishan AU, Ma TM, Lamb JM, et al. Magnetic Resonance Imaging–guided vs Computed Tomography–guided stereotactic body radiotherapy for prostate cancer: The MIRAGE randomized clinical trial. JAMA Oncology. 2023;9:365 373.

2. Keall P, Nguyen DT, O'Brien R, et al. Real-time image-guided ablative prostate cancer radiation therapy: Results from the TROG 15.01 SPARK trial. Int J Radiat Oncol Biol Phys. 2020;107:530-538.

3. Jin J-Y, Yin F-F, Tenn SE, Medin PM, Solberg TD. Use of the BrainLAB ExacTrac X-Ray 6D system in image-guided radiotherapy. Medical Dosimetry. 2008;33(2):124-134.

4. 6DoF Robotic Motion Phantom: https://github.com/Image-X-Institute/6-DoF-Robotic-Motion-Phantom.

5. Colvill E, Booth J, Nill S, et al. A dosimetric comparison of real-time adaptive and non-adaptive radiotherapy: A multi-institutional study encompassing robotic, gimbaled, multileaf collimator and couch tracking. Radioth Onc. 2016;119(1):159-165.

1078

Digital Poster

Determination of margins for intrafractional motion in online adaptive radiotherapy for pancreas

Takahiro Iwai 1 , Hiraku Iramina 1 , Michio Yoshimura 1 , Mitsuhiro Nakamura 1,2 , Ayaka Ogawa 1 , Yuka Ono 1 , Takashi Mizowaki 1 1 Kyoto University Graduate School of Medicine, Radiation Oncology and Image-Applied Therapy, Kyoto, Japan. 2 Kyoto University Graduate School of Medicine, Advanced Medical Physics, Kyoto, Japan

Purpose/Objective:

In a previous study, we demonstrated that reducing the planning organ at risk volume (PRV) margins with fiducial marker matching led to improved local control, but increased gastrointestinal toxicities (1). As a result, we decided to adopt a PRV margin of 10 mm for the stomach and 5 mm for the duodenum.