Abstract
Progress in our understanding of the molecular biology of neoplasms has been driven by remarkable improvements in molecular biology techniques. This has created a rapidly moving field in which even subspecialists struggle to keep abreast of the current literature. Nowhere is this more clearly demonstrated than in neuro-oncology, wherein molecular diagnostics can now wring more clinically useful information out of very small biopsies than ever before. Herein the biologic and practical aspects of four key molecular biomarkers in gliomas are discussed, including two that have been known for some time (1p/19q codeletion and EGFR amplification) as well as two whose relevance was discovered via advanced whole-genome assays (IDH1/2 mutations and BRAF alterations).