The Management and Outcomes of Butterfly Gliomas at a U.K. Neurosurgical Unit

AIMS Butterfly glioblastomas (bGBM) are a rare subset of WHO grade IV tumours, that carry a poor prognosis with a median survival ranging between 3 to 6 months. Our study aims to add to the literature on how these tumours should be best managed when presenting to a neurosurgical unit. METHOD We performed a retrospective analysis from January 2009 to June 2021 of the electronic patient records of single large neurosurgical centre in London. We assessed patient demographics, initial clinical presentation, tumour characteristics (location, mutation, volumetric size), clinical management and overall survival (Kaplan-Meier estimator). RESULTS 42 cases of bGBM were identified. These patients were managed with radiotherapy alone (n=3), with biopsy +/- adjuvant therapy (n=36) or attempted surgical resection (n=3). A further 38 cases of suspected bGBM were identified based on presentation and radiological imaging, however these patients were managed conservatively and did not undergo tissue diagnosis. No significant difference in survival was seen between conservative management compared to biopsy alone, with radiotherapy only or chemotherapy only (P=0.499) However, survival was significantly increased when patients received adjuvant chemoradiotherapy following biopsy or resection (P=0.04). CONCLUSION Butterfly glioblastoma has a devastating prognosis. Our study would suggest that unless a patient completes full adjuvant therapy with both chemotherapy and radiotherapy following biopsy or resection, they should be managed conservatively. This avoids unnecessary procedural interventions and can be deemed cost saving to the NHS. A larger prospective cohort study is recommended.