TERT and central nervous system cancer: Recent advancements in genome sequencing studies have led to the classification of glioma into several subtypes based on the mutation status of isocitrate dehydrogenase (IDH) and histone H3 genes, telomerase reverse transcriptase (TERT) promoter mutation, epidermal growth factor receptor (EGFR) amplification and 1p/19q deletion [2–4].