ESTRO 2024 - Abstract Book

S4634

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

ESTR0 2024

[1] N. Wahl, P. Hennig, H. P. Wieser, e M. Bangert, «Efficiency of analytical and sampling-based uncertainty propagation in intensity-modulated proton therapy», Phys. Med. Biol., vol. 62, fasc. 14, pp. 5790–5807, giu. 2017, doi: 10.1088/1361 6560/aa6ec5. [2] Z. Perkó, S. R. van der Voort, S. van de Water, C. M. H. Hartman, M. Hoogeman, e D. Lathouwers, «Fast and accurate sensitivity analysis of IMPT treatment plans using Polynomial Chaos Expansion», Phys. Med. Biol., vol. 61, fasc. 12, pp. 4646–4664, giu. 2016, doi: 10.1088/0031-9155/61/12/4646.

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Digital Poster

SBRT for small renal tumours - a dosimetric comparison using VMAT, CK and protons

Harshani Green 1,2,3 , Orla Byrne 4 , Julia Henderson 4 , Pravesh Bhudia 3 , Vasilios Rompokos 4 , Andrew Gosling 3 , Colin Baker 3 , Daniel Henderson 5 , Anita Mitra 6 , Vincent Khoo 1,2 1 Royal Marsden NHS Foundation Trust, Oncology, London, United Kingdom. 2 Institute of Cancer Research, Radiotherapy, London, United Kingdom. 3 University College London Hospitals NHS Foundation Trust, Proton Beam Therapy, London, United Kingdom. 4 Royal Marsden NHS Foundation Trust, Physics, London, United Kingdom. 5 Queen Elizabeth Hospital Birmingham, Oncology, Birmingham, United Kingdom. 6 University College London Hospitals NHS Foundation Trust, Oncology, London, United Kingdom

Purpose/Objective:

Stereotactic body radiotherapy (SBRT) is now a recognised curative-intent treatment option for inoperable localised Renal Cell Carcinoma (RCC). 5-year data demonstrate comparable cancer-specific survival to other recognised treatment options including thermal ablation (92% at 5-years) [1]. This is particularly important given these patients are likely to be older, frail and/or have other medical conditions that preclude them from surgery. Data show low severe toxicity rates of RCC SBRT; ≥CTCAE Grade 3 toxicity is 1.3% [2]. Grade 1-2% rates of toxicity are higher, up to 38%, and can include tiredness, pain, nausea and gastrointestinal toxicity. Renal function declines with SBRT at a similar rate to other nephron-sparing treatment modalities and there is a dose-response relationship; reduction of eGFR by 14ml/min per 1.73m2 by 5 years[1, 3]. Kidney dialysis rates post-SBRT are 3.7% and are more likely when the baseline kidney function is poor. Data comparing different delivery platforms may support the development of patient-selection tools to personalise care and minimise side effects, particularly in those with underlying medical conditions and/or poor renal function. There is minimal data comparing different treatment platforms for SBRT in RCC. Small clinical case cohorts of particle therapy in RCC show promising feasibility and comparable efficacy rates to photons, with low toxicity [4, 5]. A retrospective observational dosimetric analysis of primary RCC SBRT was carried out in small RCCs using three treatment platforms across 2 institutions: C-arm linear accelerator-based volumetric modulated arc therapy (VMAT), Cyberknife (CK) and pencil-beam scanning (PBS) proton beam therapy (PBT).