ESTRO 2024 - Abstract Book

S4891

Physics - Quality assurance and auditing

ESTRO 2024

Material/Methods:

Dosimetry in our department is performed by radiotherapy technologists (RTTs). All plans are reviewed by a medical physicist who, if necessary, will make modifications to the plan to improve its quality. Subsequently, all cases are presented at a dosimetry peer review session in which medical physicists (including in training ones) participate. A database in REDCap records: pathology treated, technique, modifications made during the independent review, the cause of the change, and whether the planning is optimal or there is still room for significant improvement. Modifications are classified as major (the initial plan does not comply with the oncologist's prescription or, even if it does, allows for significant improvement) or minor (the initial plan complies with the prescription, but there is room for improvement). Using the REDCap platform, 2392 treatments carried out between 01/01/2021 and 31/12/2022 were collected. All were planned using ECLIPSE (Varian vs 15.6.05). The number of treatments according to pathology and technique are shown in Figure 1.

Results:

Modifications were performed in 29% of cases, with major modifications in only 9%. However, as shown in Figure 1, there was considerable variation in the rate of changes according to pathology, ranging from 16% for prostate to 45% for breast with lymphatic areas.

The locations in which most planning modifications were made coincide with those that are most difficult to standardise (planning guidelines or introduction of automatic planning). This is due to the inherent complexities of