ESTRO 2024 - Abstract Book

S5603

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

ESTRO 2024

1 University College Cork, Medical Imaging and Radiation Therapy, School of Medicine, Cork, Ireland. 2 Bon Secours Radiotherapy, in Partnership with UPMC Hillman Cancer Centre, Cork, Ireland

Purpose/Objective:

This study aimed to provide a comparison of tattoo-based set-up against surface guided radiotherapy (SGRT) setups by performing an assessment of systematic and random setup errors in all translational directions for patients with prostate cancer treated in a single institution.

Material/Methods:

Thirty-eight patients were selected for this study. Data was collected from Aria® Oncology Information System, and the analysis was performed using Microsoft Excel.

Results:

The population systematic error on kV/kVs for SGRT was 0.11cm (lateral), 0.40cm (long) and 0.24cm (vertical). The population systematic error on kV/kVs for tattoo set-up was 0.21cm (lateral), 0.23cm (long) and 0.26cm (vertical).

Population random error on kV/kVs for SGRT was 0.15cm (lateral), 0.36cm (long), 0.22cm (vertical). Population random error on kV/kVs for tattoo setups was 0.21cm (lateral, 0.30cm (long) and 0.35cm (vertical) (Table 1).

The population systematic error on CBCT for SGRT was 0.03cm (lateral), 0.03cm (long) and 0.05cm (vertical). The population systematic error on CBCT for tattoo set-up was 0.08cm (lateral), 0.12cm (long) and 0.06cm (vertical). Population random error on CBCT for SGRT was 0.02cm (lateral), 0.03cm (long), 0.05cm (vertical). Population random error on CBCT for tattoo setups was 0.08cm (lateral), 0.14cm (long) and 0.15cm (vertical) (Table 2).