ESTRO 2024 - Abstract Book

S88 ESTRO 2024 Even though most of these cases are managed with surgery alone, the functional and cosmetic outcome of patients can be impaired. About 5% of KC will need to undergo complex and challenging treatments since they are considered high risk or are locally advanced. Such cases have a propensity for loco-regional recurrence and metastases, resulting in substantial morbidity, mortality, and a further deterioration of QoL. The QoL of KC patients can be affected by various factors such as tumor extent, treatment type and its side effects, disruption of daily activities, future cancer worries, cosmetic burden, cost, and functional limitations. Considering that the most common KC location is the head-neck region, cosmesis and function issues can lead to substantial psychosocial comorbidity, stress, and social withdrawal. Therefore, a good cosmesis and improved QoL should be ultimate goals of KC patient management. Several tools and questioners such as the DLQI, SCI, Skindex, BaSQoL and VAS are available for assessing the QoL of KC patients. However, they are limited by the fact that they can assess only certain aspects of QoL or have included patients managed with selected therapeutic options e.g., surgery only. There is no single QoL questionnaire that could be used in clinical trials, so patients are currently asked to complete multiple QoL questionnaires. Therefore, there is a need for the development of a new QoL instrument for holistically assessing the specific QoL issues in the whole spectrum of patients affected by KC. Cosmetic outcomes are frequently reported in the scientific literature since a good aesthetic result is important especially in female patients. The advances and evolution of RT techniques and surgical procedures have improved cosmetic outcomes. Changes in pigmentation occur more commonly in patients managed with radiation or imiquimod cream and the cosmetic outcome is less satisfactory in the event of multiple skin tumors. In a recent meta-analysis comparing the outcomes between External beam radiotherapy (EBRT), Brachytherapy (BRT), Mohs Micrographic Surgery (MMS) and Conventional Excision (CE) the cosmetic result was the main factor for treatment modality choice since the local control rates were similar. Moreover, patients with T1/2 KC tumors managed with BRT and MMS had improved cosmesis over EBRT and CE. No significant differences for ‘Fair’ or ‘Poor’ cosmesis was reported between groups. The most common system used for reporting Cosmesis in the scientific literature is grading by ‘Good’, ‘Fair’, ‘Poor’. In some studies, the RTOG grading system was used: “Good” corresponds to grades 0-1, “Fair” to grade 2, and “Poor” to grades 3-5. The problem with these assessment tools is that evaluations are subjective and reported study results are heterogeneous and inconclusive. Additionally, comparisons across clinical studies cannot be made. Therefore, as in the case of QoL evaluation, there is a need for the development of a validated KC specific tool that will be universally used for assessing cosmetic outcomes. Invited Speaker

3473

Radiation-related toxicity: Where do we stand and where do we go from here?

Dirk De Ruysscher

Maastro, Radiation Oncology, Maastricht, Netherlands

Abstract:

Historically, radiation was primarily seen as a DNA-damaging agent that causes different types of damage. This includes damaged DNA bases and single and double strand breaks. As consequence, side effects were thought as