ESTRO 2024 - Abstract Book

S1480

Clinical - Lower GI

ESTRO 2024

Conclusion:

IOV remains a challenge in LRRC amongst ROs and is also observed in radiologists. Overall IOV of ROs improved with a gold standard, but improvement was not detected in individual cases. As clinical impact varied, especially in fibrotic and anastomotic recurrences and recurrences located in an abscess, the role of radiological support in LRRC delineation should be further investigated. Contouring uncertainty should be a topic of discussion in expert multidisciplinary teams prior to CRT treatment.

Acknowledgements : We want to thank all participating radiologists for their delineation efforts, namely Dr. Gielens, Dr. Daniels, Dr. Nederend, Dr. Laheye, Dr. Lambregts, Dr. Oei, Dr. Houwers, Dr. Horsthuis.

Keywords: LRRC; Inter-observer variation; Delineation

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