ESTRO 2024 - Abstract Book

S5162

Radiobiology - Immuno-radiobiology

ESTRO 2024

Lymph node irradiation significantly increases the risk of developing acute RIL. Increased dosage and fractionation raise the risk of RIL to a lesser degree. There can be a rise in ALC at the beginning of radiotherapy, which declines with proceeding fractions. This information aids in determining which factors play a role in affecting ALC in particle therapy and is particularly relevant to the global advancement of immunotherapy research and implementation. To our knowledge, this is the first study that investigates lymphopenia in prostate cancer with proton radiotherapy with varying treatment plans, providing a comprehensive insight into the changes of ALC, however, additional research is required for a more in-depth assessment.

Keywords: Lymphopenia, prostate, protons

References:

1. Y. Cho, S. Park, H. K. Byun, C. G. Lee, J. Cho, M. H. Hong, H. R. Kim, B. C. Cho, S. Kim, J. Park, and H. I. Yoon, “Impact of Treatment-Related lymphopenia on immunotherapy for advanced Non-Small cell lung cancer,” International Journal of Radiation Oncology, Biology, Physics, vol. 105, pp. 1065–1073, Dec. 2019

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Digital Poster

Oxygen in anesthesia can block anti-tumor immunity and FLASH effect in proton beam irradiations

Lorea Iturri 1 , Annaïg Bertho 1 , Charlotte Lamirault 2 , Elise Brisebard 3 , Marjorie Juchaux 1 , Cristèle Gilbert 1 , Julie Espenon 1 , Catherine Sebrie 4 , Laurene Jourdain 4 , Ludovic De Marzi 5,6 , Frederic Pouzoulet 2 , Jane Muret 7 , Pierre Verrelle 5,8 , Yolanda Prezado 1 1 Institut Curie, CNRS UMR3347, Inserm U1021, Signalisation Radiobiologie et Cancer, Orsay, France. 2 Institut Curie, Translational Research Department, , Experimental Radiotherapy Platform (Radexp), Orsay, France. 3 INRAE Oniris, UMR703 PAnTher − APEX, Nantes, France. 4 CEA, Service Hospitalier Frederic Joliot, BIOMAPS Universite Paris Saclay,, Orsay, France. 5 Institut Curie, Radiation Oncology Department, Orsay, France. 6 Institut Curie, Inserm U1288, Laboratoire de Recherche Translationnelle en Oncologie (LITO), Orsay, France. 7 Institut Curie, Department of Anesthesia and Intensive Care, Paris, France. 8 Institut Curie, Inserm U1196, CNRS UMR9187, Chimie et Modélisation pour la Biologie du Cancer (CMBC), Orsay, France

Purpose/Objective:

Radiation-induced neurocognitive dysfunction is a major adverse effect of brain radiation therapy and has specific relevance in pediatric oncology, where serious cognitive deficits have been reported in survivors of pediatric brain tumors. Moreover, many pediatric patients receive proton therapy under general anesthesia or sedation to guarantee precise ballistics with a high oxygen content for safety. We aimed first to address the relevant question of the potential effect of supplemental oxygen administered during anesthesia on normal tissue toxicity and second, investigate the anti-tumor immune response generated following conventional and FLASH proton therapy.

Material/Methods: