ESTRO 2024 - Abstract Book

S4671

Physics - Optimisation, algorithms and applications for ion beam treatment planning

ESTR0 2024

Mean tumour dimension was 6.8cm and mean target volume was 365cm 3 . Results show CIRT and PBT met OAR dose constraints (see median doses in Table 1).

Median small bowel D1cc was 39.97Gy(RBE) and 37.65Gy(RBE) for CIRT and PBT respectively. Ranges are presented in Table 1. Median duodenum D2cc was 23.03Gy(RBE) and 23.67Gy(RBE) for CIRT and PBT respectively. Median large bowel D1cc was 30.05Gy(RBE) and 26.77Gy(RBE) with PBT respectively. Median spinal cord D1cc was 2.71Gy(RBE) and 3.35Gy(RBE) for CIRT and PBT respectively.

Conclusion:

RCC radiotherapy is dosimetrically feasible using particle therapy. Similar dosimetry was achievable with the two techniques in this study in these large and challenging cases. However, in some scenarios, the field angles facilitated by the proton gantry were potentially beneficial over fixed-beam CIRT in sparing large bowel and meeting OAR constraints. In cases of significant overlap with bowel, it was challenging to meet OAR constraints with both techniques. Further research is required to identify patient selection tools e.g. tumour diameter, proximity to OARs and particular medical comorbidities, for when particle therapy may be of benefit. Collaborative work is ongoing to optimise motion management and imaging required for precise delivery of clinical studies investigating particle therapy in RCC.

Acknowledgements:

NIHR RMH Biomedical Research Centre

Keywords: Carbon ion, proton beam, renal cell carcinoma

References:

1. Correa, R.J.M., et al., Stereotactic Radiotherapy as a Treatment Option for Renal Tumors in the Solitary Kidney: A Multicenter Analysis from the IROCK. J Urol, 2019. 201(6): p. 1097-1104.