BRAF and central nervous system cancer: A 2015 population-based study found that while only 2.9% of pLGGs transformed to secondary high grade gliomas (sHGG), BRAF V600E mutations were present in 44% (8 of 18) of pLLGs that transformed to sHGG as compared to 6% (10 of 167) of pLGGs that did not transform (5, 6, 8).