ESTRO38 Congress Report

Introduction Radiobiology track

There were ninety Radiobiology abstracts submitted to ESTRO 38, scored by a minimum of six independent reviewers. Interestingly, more than 10% of abstracts came from Asia. Twenty- seven abstracts were selected for oral presentation, 8 for poster viewing and the remainder for

Many new developments in preclinical animal models were presented at ESTRO 38 including a new bladder cancer model, particle irradiation in small animals, and zebrafish as a preclinical RT model. Biological response to particle irradiation was considered in a separate symposium, as well as discussing protons, carbon-ions and neutrons. An emerging topic in an interdisciplinary symposium was on how the microbiome influences cancer progression and treatment response, which was likely to influence personalised treatment. Hope you enjoyed your meeting in Milan with lots of stimulating discussions. Marc Vooijs Chair, SAG Radiobiology

MARC VOOIJS

e-posters and regular posters. The Biology track featured six symposia four teaching lectures and one debate. Radiation biology was represented in more than half of the interdisciplinary sessions and there also was a Biology pre-meeting on Cell Death. An increasing number of abstracts were submitted on novel ways to exploit the immune system in combination with radiotherapy. Topics ranged from the identification of novel immune stimulatory signals from tumour cells and suppressive signals from the tumour microenvironment, to novel combination treatments enhancing checkpoint inhibition with radiotherapy, as well as using ultrasound to enhance radiotherapy. Several proffered presentations were selected to follow an exciting symposiumon immunogenic cell death and radiotherapy and an interdisciplinary symposium on radioimmunotherapy. At the end of ESTRO 38 there was a critical debate on immunotherapy: "evolution or revolution” for radiotherapy. Thereweremany interesting studies but some nice examples are described in the next section of this report: the REQUITE study by Christopher Talbot et al; the use of TEMPRSS2:ERG byWael Mansour et al to identify vulnerability for combining PARP inhbition and radiation in ERG overexpressing prostate cancers in preclinical and patient studies and the study by Dan Ou et al where a large number of CT images from patients with head and neck cancer was analysed and corelated to a prognostic radiomics signature based and HPV status with immune infiltration phenotype in these tumors using IHC from biopsies. Tumour metabolismand the DNA damage response are both topics that returned at ESTRO 38. This year we presented a dedicated symposium on the cellular determinants of the radiation response. With O2 being one of the most potent radiation sensitisers, several presentations are on hypoxia modification strategies, redox signalling and on gender-specific metabolism and treatment outcome. A related symposium was on the topic of imaging tumour metabolism in cells and in vivo. This year there was also a lot of interest in biomarkers to predict radiotherapy response and an entire symposium dedicated to development and application of liquid biopsies in radiotherapy. There was also a lot of interest in normal tissue responses. Work was presented describing the identification of susceptibility loci for late toxicity after prostate cancer radiotherapy and the influence of mitochondrial DNA variation on lung toxicity. Poster presentations and proffered papers discussed the effects of radiation therapy on human stem cells in the lung, the hair follicle and on mesenchymal stem cells, and, in a preceding symposiumon the effects of irradiation on stem cells compartment in vivo, in the salivary gland and brain.

Congress report | RADIOBIOLOGY

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