ESTRO 2025 - Abstract Book

S58

Invited Speaker

ESTRO 2025

geriatric assessment and clarifying the patients’ outcomes. A multidisciplinary team approach is paramount. The standard guidelines that are referred to for Geriatric patients include those by the ASCO and NCCN. It may be prudent to say that these may not be applicable globally. The basic principles include: While dealing with early HN cancer, the goal should be to provide the best treatment with effective outcomes and the least toxicity. This can be applied to other sites, too. While considering more advanced diseases, the principle of effective trade-off comes into play. The cure has to be balanced against toxicity and QoL. A classic example is the use of concurrent chemotherapy in locally advanced head and neck tumors, where there is a decreasing effect of chemotherapy with increasing age, especially in patients above 71 years. The proportion of deaths not due to head and neck cancer increases from 18% to 37% in patients > 70 years, and this was also observed in the MACH-NC metaanalyses. This also highlights the importance of comorbidity and other concomitant factors in treating the elderly and their impact on outcomes when choosing standard or modified treatment schedules. These essential modifications would necessitate modifications in radiotherapy doses, schedules, and concurrent treatments, which could, in turn, lead to different outcomes in this population. A few largely retrospective studies have evaluated treatment, especially in older people, looking at compliance, toxicity and outcomes. They have concluded that although oncological outcomes of elderly head and neck cancer patients were similar, treatment-related toxicities were higher in elderly patients. Radiation alone can be considered for elderly patients, given concerns with toxicities. Hence, the use of concurrent CTRT in elderly LAHNC patients needs to be given special consideration. Comorbidities and physiological age may be better predictors. In a retrospective review of RTOG studies by Mitchell Machtay et al., age, stage, and tumor site were strong predictors of late severe toxicity. The impact of multimodality therapy in the adjuvant setting is also evident in patients of advanced age who are not doing well with combined modality treatments. As a radiation oncologist, various other considerations for the geriatric group include the dose, duration, technique and treatment intent. Instead of conventional fractionation, various HFRT (hypofractionated EBRT) regimes have been considered. They may offer several advantages like reduced overall treatment time, equivalent radiobiological effectiveness for tumor control rate and toxicity, leading to enhanced survival outcomes, reduced number of hospital visits as well as hospital expenses with enhanced patient convenience and compliance. Tailoring therapy to the individual, with shared decision-making and appropriate considerations of the stage and extent of disease, comorbidities, and other social factors, may be the cornerstone to successful outcomes in this group of patients.

This talk will discuss evidence for and against the standard treatments and our experience.

4741

Speaker Abstracts Robust quantitative MRI parameter extraction for clinical multicentre trials Faisal Mahmood Dept. of Oncology, Odense University Hospital, Odense, Denmark

Abstract:

Quantitative MRI biomarkers hold significant promise for improving radiotherapy response assessment, yet their widespread adoption in multicentre clinical trials is hampered by variations in acquisition protocols and analysis methods. This talk addresses the challenge of intra-site and inter-site variability by outlining the sources of variation