ESTRO 2024 - Abstract Book

S4179

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

ESTRO 2024

Results:

Three hundred forty online sessions were analyzed of which 68%, 91% and 13% of the sessions had manual corrections to the propagated GTV, bladder and rectum delineations, respectively. The CTV boost delineations from plan auto differed from plan clin with a median DSC of 0.71, a 95%HD of 7 mm and a relative volume of 78% (Fig. 1). The median differences between the bladder delineations from plan clin and plan auto were given by a DSC of 0.92, a 95%HD of 5 mm and a relative volume of 92%. For the rectum this was 0.99, 4 mm and 100%, respectively. Comparing the dosimetric consequences between plan clin and plan auto resulted in a median difference in target coverage of 0.42% for CTV boost and 0.03% for CTV elective (Fig. 2). The clinical requirement was met by 65% of the sessions for CTV boost and 95% of the sessions for CTV elective . For 15 out of 17 patients, the CTV elective coverage met the clinical requirement in all sessions. Statistical analysis shows a significant difference between plan auto and plan clin for both CTV boost and CTV elective coverage (p<0.05).

Conclusion: