ESTRO 2023 - Abstract Book

S423

Sunday 14 May 2023

ESTRO 2023

iii/ deploying an integrated artificial intelligence (AI)-based treatment planning system that automatically integrated immune constraints and iv/ exploring the potential of pharmacological immune support based on an IL-15 superagonist immunomodulation. The proof of concept will be made in head and neck squamous cell carcinoma, although our vision is to deliver novel clinically validated tools with scalable application in multiple cancer types and stages. In parallel, we will leverage immuno-RT possibilities to the next level to render it a reliable and easy- to-implement option for oligometastatic cases who could be candidates to non-invasive ablative treatment, e.g. in intent to cure. In the first place, this approach implies to improve patient selection and even more precisely, intra-patient lesion selection among target lesions that could either respond or not to immunotherapy, using radiomics-based prediction. Then, our plan is to move further the ‘one patient one dose’ dogma, and build a lymphocyte-sparing multi-target holistic treatment selection pathway, enabling ultra-personalised treatment of solid cancers.

Award Lecture: Iridium 192 Award

SP-0516 I have a dream... G. Kovács 1 1 Università Cattolica del Sacro Cuore, Gemelli-INTERACTS, Rome, Italy

Abstract Text Cancer treatment, especially the treatment of a localized tumor volume, developed extremely fast in the past decades. This improvement is based mainly on technical developments but also on the understanding that fair and quick multidisciplinary cooperation is crucial in treatment success and patient well-being. Furthermore, economic issues have become more critical worldwide than in the past. A new branch of cancer care called "Interventional Oncology (IO)" has been introduced and gaining more and more field in the literature - and clinical practice. IO is a multidisciplinary treatment for localized cancer burden (primaries or metastases) using minimally invasive procedures performed under image guidance. It describes a specialty where various experts of different kinds of interventional methods are building a team to offer the best-personalized treatment for eligible patients. Members of a successful IO team are open-minded and cooperating experts in interventional radiotherapy (brachytherapy), interventional radiology, interventional endoscopy, and interventional chemotherapy. At the time being, IO is considered the fourth pillar of modern cancer care. Regarding interventional radiotherapy (brachytherapy), the roots go back to the pioneer times of radium treatments. Multiple schools worldwide, sometimes with different treatment philosophies, were established, and members of the schools were active in clinical practice, research, and educating the follower generations. Looking back to the past 45 years of interventional radiotherapy (brachytherapy), we see great successes, some failures, and changes in the acceptance – but a straight rise and development of the specialty. Focusing on interventional radiotherapy, we made significant steps forward in improving treatment outcomes and optimizing or establishing research and educational structures within National Societies and on the European stage – but we also stopped sometimes for a while. Nevertheless, we notice extensive development, and we also can state the growing interest and rising research success of the next generation. For continuous success, however, it is advisable to remember the wise statement of Rosenbaum et al.*: "Given the expectations for better care at lower cost motivating changes, the lack of a shared definition of value is potentially destructive. If we can simultaneously improve quality and cut costs, it will first require a look at the whole picture — and then a willingness to believe what we see". *Rosenbaum L, NEJM 2013; DOI: 10.1056/NEJMms1301576

Joint Symposium: ESTRO-ESC: New cardio-oncology guidelines: Current state of knowledge and future directions

SP-0517 – 0520

Abstracts not available for this session

Symposium: Individualising radiotherapy dose according to normal tissue effects - Are we there yet?

SP-0521 Functional assays to predict individual patient responses to radiotherapy M. Bourguignon 1 1 University Paris Saclay, Biophysics and Nuclear Medicine, Montigny le Bretonneux, France

Abstract Text Radiosensitivity is a clinical issue for oncologists who face early and late post-RT abnormal tissue response with a variety of severity syndromes quantified with a grading system notably the CTCAE (Common Terminology Criteria for Adverse Events) of the National Cancer Institute: from 15 to 20% of patients present significant tissue effects (grades 2 to 5). The radiosensitivity is related to cell deaths and thus quite different from individual radiosusceptibility to cancer related to transformed cells and radiodegeneration related to tissue degeneration. These events are mostly encountered after RT of head and neck carcinoma, breast, lung, prostate and rectal cancer. Radiation oncologists already take into account known factors (diabetes, smoking…) and they wish to know unknown individual factors (abnormal DNA damage response, genetic …) and require predictive assays to adapt radiation therapy protocols to prevent these adverse events. Clinical radiosensitivity has been quantified for years with in vitro cell surviving fraction at 2Gy (SF2). It has demonstrated intrinsic radiosensitivity since cell survival curves never cross with a continuum in radiation responses from normal to highly abnormal. So far up to 30 genetic diseases have been identified to present individual radiosensitivity. A statistically significant correlation between clonogenic cell survival (SF2) and CTCAE grades has been established for both these genetic