ESTRO 2024 Congress report
Considering the growing interest in the upright position for radiotherapy, the physics scientific advisory group of ESTRO 2024 proposed this symposium.
Five speakers – four physicists and myself (an RTT) addressed the question through a discussion of the potential benefits and ongoing challenges of the upright position in radiotherapy, especially for particle therapy.
Ye Zhang, from the Paul Scherrer Institute, Switzerland, began her presentation by putting forward the fact that the use of upright radiotherapy would remove the need for gantries and reduce the space needed for a particle therapy system by nearly 80%. This implies a decrease in treatment facility costs, which Dr Zhang explained would increase the proportion of patients who could be treated with particle therapy. Currently, about 1% of patients receive it, while 15% could benefit (1). Moreover, advanced treatment methods, such as proton arc therapy, combined proton-photon treatment or the use of MR guidance, are integrated by removing the gantry. Dr Zhang also presented several ongoing projects that were aimed at providing more data on clinical changes between upright and supine positions. However, the potential clinical benefits are under-investigated.
The concept of upright radiotherapy is not new, as Lennart Volz from GSI Helmholtz Centre for Heavy Ion Research, Germany, pointed out. He presented the ongoing challenges, explaining that every step of the patient health care pathway (imaging, treatment planning, segmentation, quality assurance (QA) and treatment delivery) was impacted by upright position. However, several companies have recently increased their interest in the development of upright imaging devices, which are needed to study anatomical changes between upright and supine positions. As a result, Dr Volz added that tools and concepts, such as auto-contouring, the margins recipes and QA equipment, would have to be adjusted. He concluded his talk with: “Upright radiotherapy has a lot of potential, but many challenges remain. The most crucial challenge is that we need more data, more evidence to support the different decisions that have to be taken for upright radiotherapy.”
After these two talks, I shared my experience and introduced data from the literature on patient perspectives, treatment position accuracy and set-up time. I presented a study of 16 pelvis cancer patients who had been set up three times in the upright positioner that had been developed by Leon Cancer Care. Some of them reported pain and difficulties during their placement into or arising from the supine position, which they did not experience in the upright position (2). For breast cancer patients, seven of nine patients who tested the upright positioner for 40 minutes preferred the upright position compared with the supine position (3). Then, I spoke about set-up time, reproducibility and stability. The available data are promising; however, we need more data on various localisations and data from 3D images to know whether the organ position is reproducible and stable.
As few clinical upright systems have yet been used to treat patients, Mark Pankuch from the Northwestern Medicine Proton Center in Chicago, USA, was able to present his experience with the system developed by P-Cure. The system includes an upright CT scanner and two chairs, one for the thoracic area and another for cranial treatment, which are installed to be able to deliver gantry-type treatments without a gantry system.
Finally, Thomas Bortfeld from Massachusetts General Hospital, USA, showed us some advanced treatment concepts that could be facilitated through the use of upright radiotherapy and could democratise particle therapy. This is a case of strategies using image guidance with the opportunity to develop MRI-guided proton therapy. Dr Bortfeld concluded the symposium by saying that hype was not desirable for upright radiotherapy, even though the interest in the topic was much appreciated. However, there is also hope, and now we need to define a strategy to move forward.
Sophie Boisbouvier
Radiation therapist, MSc
Léon Bérard Center
Lyon, France
ESTRO P&I focus group
- Yan S, Ngoma TA, Ngwa W, Bortfeld TR. Global democratisation of proton radiotherapy. Lancet Oncol [Internet]. 1 juin 2023;24(6):e245‑54. Available at : https://www.thelancet.com/journals/lanonc/article/PIIS1470-2045(23)00184-5/fulltext
- Boisbouvier S, Boucaud A, Tanguy R, Grégoire V. Upright patient positioning for pelvic radiotherapy treatments. Tech Innov Patient Support Radiat Oncol [Internet]. déc 2022;24:124‑30. Available at: https://linkinghub.elsevier.com/retrieve/pii/S2405632422000488
- Boisbouvier S, Underwood T, McNamara J, Probst H. Upright patient positioning for gantry-free breast radiotherapy: feasibility tests using a robotic chair and specialised bras. Front Oncol [Internet]. 2023;13. Available at: https://www.frontiersin.org/articles/10.3389/fonc.2023.1250678