Challenges facing level I evidence in treatment of low-grade gliomas and subsequent uncertainties

The current era of molecular characterisation has contributed greatly to our understanding and management of low-grade gliomas (LGGs); however, this has also contributed to a paucity in level 1 evidence. Diagnostic breakthroughs in LGGs are moving quicker than our experimental capacity can react. The design, analysis, and clinical application of first-level evidence are struggling to compete with the considerable variability in the natural course of LGGs and the rapidly evolving utility of molecular characterisation of tumours. This poses several uncertainties to researchers, clinicians, and more importantly, patients. Individualised case-by-case decisions based on best available evidence, albeit lacking level 1 evidence, must be made by considering the tumour behaviour, clinical course, and specific patient needs and goals.