ESTRO 2024 - Abstract Book

S5480

RTT - Patient care, preparation, immobilisation and IGRT verification protocols

ESTRO 2024

4. Sebastian Sarudis, Anna Karlsson Hauer, Jan Nyman & Anna Bäck (2017) Systematic evaluation of lung tumor motion using four-dimensional computed tomography, Acta Oncologica

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6. Cravo Sá A, Fermento A, Neves D, Ferreira S, Silva T, Marques CC, et al. Radiotherapysetup displacements in breast cancer patients: 3D surface imaging experience. Rep Pract Oncol Radiother. 2018;23:61-7.

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Comparing setup errors in right breast radiotherapy patients: Tattoo Vs. Surface Guided Radiotherapy

AYA AL ZEEDI, fatema albalushi

Sultan Qaboos Comprehensive Cancer Care and Research Centre, Radiation Oncology, Muscat, Oman

Purpose/Objective:

Conventionally, tattoos are used to achieve a reproducible patient setup during a radiotherapy treatment. With the introduction of surface guided radiotherapy (SGRT), the use of tattoos could become less common in breast cancer patients which can be quite promising in the Middle East due to the psychological, cultural and religious practices that challenge the use of tattoos in this region. With the use of real-time tracking, SGRT may potentially result in more accurate and efficient positioning compared to the traditional tattoo-based treatment. The aim of this study is to compare the systematic and random errors between patients positioned with tattoos and those positioned with SGRT in Right (RT) breast cancer patients using values acquired from cone beam computed tomography (CBCT) images.

Material/Methods:

20 RT Breast/chest wall cancer patients were selected for this study. 10 CBCT images were acquired per patient for daily online set-up verification. For 5 sessions the patients were positioned with tattoo and for the other 5 sessions they were positioned with SGRT (1) . All 200 CBCT exposures were analysed according to the translational and rotational shifts which were obtained from ‘ARIA’ oncology management system along with the time taken. The means of standard deviation (SD) is taken to represent the systematic errors and the random errors is represented by the root mean square (RMS) of standard deviation (2) .

Results: