RADT-51. RADIATION-INDUCED CEREBRAL CONTRAST ENHANCEMENTS STRONGLY SHARE RISK FACTORS WITH STROKE

Abstract

Abstract BACKGROUND AND PURPOSE Radiation-induced cerebral contrast enhancements (RICE) are feared because frequent and potentially health-threatening. Risk factors are badly understood. Better understanding of RICE risk factors is critical to better face its risks by adapting therapy in the first place or patient care during follow-up. MATERIALS AND METHODS We analyzed consecutive 235 patients treated with proton radiotherapy (PRT; 54Gy RBE) for LGG from 2010 to 2020 and followed with serial clinical exams and magnetic resonance imaging for in median 5.6 years. RESULTS The risk of RICE was significantly higher in patients with vascular risk factors (VRF) (p = 0.02). Especially age ≥50 years (vs. adults <50 years: two-fold risk; p = 0.02), hypertension (three-fold risk; p = 0.0001) and diabetes (6.7-fold risk; p = 0.007) were shown to be clearly associated to RICE occurrence. Dyslipidemia (2.4-fold), overweight (1.3-fold) and smoking (1.3-fold) was also more frequently observed in the cohort that developed RICE. History of previous stroke went along with a 1.7-fold risk for RICE but threshold for significance was not reached. If RICE occurred, Bevacizumab treatment was two-fold more frequently needed in the cohort with VRF, but RICE prognosis did not differ relevantly between the RICE subcohort with and without VRF. CONCLUSIONS These data firstly demonstrate that RICE strongly share risk factors with ischemic stroke which further enhances our vague understanding of multifactorial pathophysiology and opportunities of tackling RICE. Classical vascular risk factors, especially age, hypertension and diabetes correlated strongly with RICE risk. Risk-adapted screening and therapy can be directly derived from this data.