P09.16.A TREATMENT OF BRAIN RADIONECROSIS: A SURVEY OF PROVISION OF CARE AND ACCESS TO BEVACIZUMAB IN THE UNITED KINGDOM

Abstract BACKGROUND Radiation necrosis (RN) in the brain, is a treatment-related effect of cranial radiotherapy that can lead to significant neurological symptoms. In symptomatic cases, steroids are often used first line. However, prolonged steroid use can lead to significant toxicity. There is a lack of consensus guidelines on further treatment options in a steroid-dependent/refractory setting. Despite the recommendation of international guidelines for use in symptomatic RN, bevacizumab is not recommended by National Institute for Health and Care Excellence in the United Kingdom (UK). We aim to review variation in the management of brain RN within neuro-oncology practice and provision across the UK. MATERIAL AND METHODS In this study, all oncology departments treating neuro-oncology departments in the UK were invited to participate. Neuro-oncology specialists completed an online questionnaire-based survey. Quantitative results were analysed using descriptive statistics, while free-text responses were used to provide contextual analysis. RESULTS The survey was completed by 37/49 neuro-oncology centres, including 23 SRS centres and represents all 30 networks. Advanced magnetic resonance imaging (MRI) techniques are used by (34/37, 92%) centres, while PET/amino acid PET is available in (9/37, 25%). Access to bevacizumab, either through local funding pathways for this patient group or through individual patient funding applications was reported by (11/37, 30%) centres. Other clinically used drugs include pentoxifylline (5/37, 14%), and Boswellia serrata in 1 centre. Most centres (10/11, 91%) with clinical experience of bevacizumab treat less than 10 patients/year and use biosimilar preparations. For symptomatic RN, the most common initial management is observation (34/37, 92%), steroids (35/37, 95%), and surgery (10/37, 27%), with bevacizumab and pentoxifylline used in 2/37 centres (5.4%). Only 1 centre would use bevacizumab in asymptomatic RN. Bevacizumab is considered an option to spare steroids toxicity in (15/33, 46%) centres, for complex steroid weaning in (14/37, 38%), and for refractory RN in (13/37, 35%). 16/28 centres (57%) do not currently have access to bevacizumab and 8/37 centres (22%) have applied for, but been refused funding. Free text answers expressed frustration at the inequality and suggested a unified national approach and funding structure to ensure equitable access for patients. CONCLUSION There is consensus on initial management of RN and most centres have access to advanced imaging in the diagnostic pathway. There is national variation in access second line treatments for RN. This survey reveals inequities in access to bevacizumab across UK neuro-oncology centres. Clinicians express concern about these disparities, highlighting the need for further evidence and policy or funding changes to standardize care for neuro-oncology patients.