ESTRO 2020 Abstract Book

S645 ESTRO 2020

Conclusion ICB is less effective in Korean patients with advanced melanoma compared to their Western counterparts due to modest response rates in non-CSD types, which account for 97% of malignant melanoma in Korea population. The present data provides a strong rationale for initiating combination immunotherapy approaches, and contributes to launch phase II study to investigate whether RT plus immunotherapy increase the level of antimelanoma activity (NCT04017897). PO-1225 Skin radiotherapy training programme for dermatology specialty trainees - an unmet need A. Rembielak 1 , T. Ahad 2 , A. Sanneh 3 1 The Christie Hospital and The University of Manchester, Clinical Oncology, Manchester, United Kingdom ; 2 Salford Royal NHS Foundation Trust, Dermatology, Salford, United Kingdom ; 3 The Christie Hospital, Radiotherapy, Manchester, United Kingdom Purpose or Objective Radiotherapy is an important modality for the treatment of skin malignancies. Although an integral part of the dermatology curriculum, exposure and knowledge in skin radiotherapy is limited amongst dermatology specialty trainees. The dermatology UK national curriculum specifies competency in the principles, indications, risks and benefits of radiotherapy and ability to construct a treatment plan for primary skin malignancy. Trainees are currently independently responsible for arranging means of fulfilling this requirement, which may be through independent study, observerships or courses as agreed with their educational supervisor. Quality of training in this field can therefore be varied and often becomes a box- ticking exercise. This can in turn affect quality of referrals made to radiotherapy clinics and limit treatment choices offered to patients. Material and Methods To address this gap in training, an innovative programme to deliver radiotherapy training in skin malignancies was designed for the UK North-Western Dermatology Deanery. The training programme consisted of a radiotherapy training day at the Christie Hospital, Manchester and participation in at least two skin radiotherapy clinics. The radiotherapy training day consisted of interactive lectures covering curriculum objectives, followed by small group practical sessions exploring radiotherapy equipment, procedures and patients’ experience. This was delivered by a multi-disciplinary team involving radiotherapy doctors, radiographers and medical physicists. The clinics included new and follow-up patients with skin cancer, skin marking planning sessions and on-treatment reviews. Results Feedback was obtained through anonymised survey responses (observership in clinics) and feedback forms (study day). Responders rated their knowledge in radiotherapy as ‘below average’ prior to the programme and as feeling ‘confident’ after the programme. Learning objectives fulfilled by the teaching programme according to the responders included indications and contraindications for skin radiotherapy, optimal patients to refer for radiotherapy, methods of delivering radiotherapy, patient compliance, management of skin toxicities, radiotherapy planning and shielding, geriatric assessment, dealing with patients who lack capacity and patients’ involvement in the decision making process. Conclusion Overall, feedback received indicated that this programme succeeded in sufficiently increasing knowledge and confidence amongst dermatology specialty trainees in skin radiotherapy. Subsequent incorporation of this programme into dermatology training and addition of regular radiotherapy clinics into the dermatology registrar rota have now streamlined training dermatology trainees receive in this field, ensuring that curriculum objectives

are properly met and patient care and referral practice is improved. PO-1226 Safety and outcomes of concurrent immunotherapy and radiation therapy for melanoma brain metastases A. Desagneaux 1 , M.T. Leccia 2 , I. Gabelle Flandin 1 , A.-.M. Dols 3 , A. Kastler 4 , J. Charles 2 , C. Verry 1 1 CHU Grenoble Alpes, Radiotherapy, La Tronche, France ; 2 CHU Grenoble Alpes, Dermatology, La Tronche, France ; 3 CHU Grenoble Alpes, Statistics, La Tronche, France ; 4 CHU Grenoble Alpes, Neuro Radiology, La Tronche, France Purpose or Objective In spite of the promising results of Immune Checkpoint Inhibitor (ICI), the development of brain metastases remains a common issue with almost systematic use of brain RT. Combined ICI and brain RT are a growing issue in the current practice. To assess the safety and outcomes of concurrent ICI and brain RT with a focus on sequencing and timing of both treatments for patients with brain This retrospective and single- institution study included all consecutive patients treated for a brain metastatic melanoma with an ICI (anti – CTLA4 or anti – PD1) and brain RT from December 1, 2010 and April 30, 2018. The concurrent group was defined by an ICI performed within 4 weeks before or after RT. Primary endpoint was neurological adverse events graded with Common Terminology Criteria for Adverse Events (CTCAE) version 5.0. Secondary endpoints were Overall Survival (OS), Distant Brain Failure (DBF) and Local Control (LC). Lesions were assessed according to the Response Evaluation Criteria in Solid Tumors version 1.1 (RECIST 1.1) [22] by MRI repeated every 3 months. Results Fifty - three consecutive patients were included. A total of 81 RT sessions were performed: 58 with Stereotactic RT (87.3% with multiple fractions) and 23 with WBRT. The majority of RT (63%, n=51) was delivered with concurrent ICI. Acute Neurological Adverse Events (AE) ≥ grade 3 occurred for 12.3% of RT session, with no difference between concurrent and non – concurrent groups. In univariate analysis, Karnofsky Performance Status score was significantly associated with ≥ grade 3 AE (p=0.018). Among SRT sessions, AE ≥ grade 3 have been recorded for 5.9% for concurrent sessions and 12.5% for non – concurrent sessions. With a median follow-up of 11.4 months, the median OS after RT was 11.5 months for the entire cohort with no difference by looking at timing. Patients treated with SRT compared to WBRT as first radiation had a median OS of 15.9 months in comparison to 2.7 months, respectively (p =0.057). OS was influenced by melanoma- mol GPA score (p=0.03). Regarding brain metastases treated by stereotactic RT (n=88), the median LC was 14.1 months with significant difference, in favor of concurrent SRT and ICI (p =0.007). One-year LC probability was higher in the concurrent group than in the non-concurrent group, respectively 72.4 % vs 38.5%. metastases melanoma. Material and Methods