ESTRO 2023 - Abstract Book

S279

Sunday 14 May 2023

ESTRO 2023

In conclusion, working with international datasets in radiotherapy can provide valuable insights into the factors that affect treatment outcomes and help to improve patient care. However, it also requires careful planning, coordination, and collaboration among researchers to harness its full potential.

Symposium: Risk-adapted personalised brachytherapy

SP-0372 Dose (de)escalation in advanced tumours: Lessons from EMBRACE I and perspectives M. Schmid 1 1 Medical University of Vienna, Department of Radiation Oncology, Vienna, Austria

Abstract Text This presentation will summarize clinical outcome of patients treated with definitive chemo-radiation and MRI based image- guided adaptive brachytherapy for locally advanced cervical cancer within the Embrace I study. Main focus will be put on risk factors for local failure and new insights into dose-response relationships for local tumour control. Recent evidence from EMBRACE I and upcoming evidence from EMBRACE II point - beyond the current strategy of individual volumetric adaptation – towards the possibility of risk-adapted treatment and personalized dose prescription. First concepts for EMBRACE III will be outlined.

SP-0373 Tumour biology to guide brachytherapy delivery and combination therapies S. Chopra 1 1 ACTREC, Tata Memorial Centre, Radiation Oncology, Navi Mumbai, India

Abstract Text In the last decade the delivery of high quality MR guided adaptive brachytherapy has led to improved local control. However, this impact is not uniform across histological types. The differences in cervical cancer biology (HPV dependent or independent or PDL-1 positive vs not, presence of hypoxia or not ) in reference to radiation response needs to be further investigated for feasibility of dose deescalation. or escalation in future trials. The first leads from international BIOEMBRACE study are available and further investigation of intratumoral and systemic immune mileiu is needed for it's potential impact on brachytherapy outcomes. This talk will focus on early observations from Phase III Akt pathway inhibitor randomised trial (Nelfinavir), and HPV/PDL-1 biology within BIOEMBRACE study. The speaker will also focus on scheduling or timing of combination of anti PDL-1, AKT and VEGF inhibitors during chemoradiation and brachytherapy in ongoing trials and soon to be initiated EMBRACE studies in locally advanced high-risk and oligorecurrent setting.

SP-0374 Non-invasive tumour characterisation: Perspectives for brachytherapy C. Robert 1 , S. Niyoteka 1 , R. Rouhi 1 , R. Sun 1 , S. Espenel 1 , C. Chargari 1 , E. Deutsch 1 1 Gustave Roussy, Radiotherapy, Villejuif, France

Abstract Text The extraction of large-scale quantitative data from medical images acquired in clinical routine (i.e. radiomics) has emerged as a gold mine for defining new biomarkers. Several studies have demonstrated its added value and complementarity to clinical and dosimetric variables conventionally used in studies aiming at predicting patient response to treatment or survival. In spite of the enthusiasm of the last ten years, several obstacles such as the non-standardization of image acquisition protocols, coupled with the heterogeneity of the available imagers, the lack of access to large multicenter cohorts, or the difficulty of accessing annotated data (segmentation of the volumes of interest in conventional radiomics), to which are added the sometimes mixed performances, have weakened this research theme, making it difficult to translate into clinical use these laboratory image-based signatures. In this context, this presentation will attempt to address the following questions: are there still blocking points for large-scale radiomics studies? What opportunities for radiomics in 2023? Should we expect clinical trials to personalize patient management in the short term or will radiomics remain the subject of ancillary studies in clinical trials? The state of the art will be illustrated on locally advanced cervical cancer for which biomarkers represent an opportunity for guiding therapeutic trade-offs, particularly at the brachytherapy treatment planning stage.

Panel Discussion: Evolutions in radiation therapist professional development

SP-0375 - 0378

Abstracts not available for this session

Mini-Oral: Paediatrics - AYA

MO-0379 Clinical Outcome of AYAs with Head and Neck Sarcomas after Pencil Beam Scanning Proton Therapy M. Vazquez 1 , A. Ilundain 1 , D. Leiser 1 , B. Bachtiary 1 , A. Pica 1 , U.L. Kliebsch 1 , D.C. Weber 1 1 Paul Scherrer Institut, Center for Proton Therapy, Villigen, Switzerland Purpose or Objective Adolescents and young adults (AYAs) with cancer constitute a subgroup of patients that face unique challenges. Head and neck sarcomas (HNSs) are rare tumors that typically require aggressive multimodal treatment, including radiation therapy. Our aim is to assess the clinical outcome of AYAs with HNS treated with pencil beam scanning proton therapy (PBSPT).