CTNI-17. NEUROSURGEONS’ PERSPECTIVE ON SURGICAL TREATMENT OF GLIOBLASTOMA: PRACTICES, BELIEFS AND WILLINGNESS TO RANDOMIZE IN SURGICAL TRIALS

Abstract BACKGROUND We conducted an international survey of neurosurgeons to explore their surgical habits, opinions on current quality of evidence, and willingness to participate in RCTs for patients with glioblastoma. MATERIALS AND METHODS The survey was distributed through EORTC, EANS and CNS as well as seven national neurosurgical societies. Chi-square test was used to assess the association between categorical variables. RESULTS Three-hundred and twenty-eight neurosurgeons (N =, 81.7% male) from 38 countries and 5 continents responded. Most (N=, 83.2%) worked in academic centers. All career stages and individual volumes of brain tumors operated yearly are equally represented in the survey. Among intraoperative adjuncts, neuro-navigation (N =, 98.5%), intraoperative neuromonitoring (80.2%), fluorescence (80.6%) and intraoperative ultrasound (60.1%) were most used. Eighty-two% of surgeons use awake surgery in less than 20% of GBM cases. The optimal goal for GBM surgery was indicated to be supramarginal resection (SM, 60.4% of surgeons) vs complete resection of enhancing tumor (CRET, 37.8% of surgeons). Significant differences in these views existed across countries (p<0.001), and female neurosurgeons tended more towards SM (71.5% vs 57.5%, p=0.02). The strength of evidence was considered “strong” to “extremely strong” in 90.2% for CRET and 63.1% for SM. A greater proportion expressed willingness to randomize to CRET vs SM (72.6%) than partial resection vs biopsy, when CRET is not feasible (49.4%). Surgeons who conveyed that evidence is currently weak were also less willing to randomize (p<0.001). Case-based evaluation showed correlation but not complete overlap between general and case-specific willingness to randomize. CONCLUSION Although the specificities of a GBM case influence decision-making, a notable proportion of neurosurgeons worldwide would be willing to participate in RCTs for surgical treatment of GBM. General impression of equipoise plays a role, but individual assessment of patient safety most likely also influences surgeons’ willingness to randomize.