CDKN2A and lung adenocarcinoma: In a recent study of 76 neurosurgical lung adenocarcinoma BM specimens, next generation sequencing of 48 cancer-associated genes identified that the most commonly mutated genes were TP53, KRAS and CDKN2A, whilst other potentially druggable alterations included EGFR, PIK3CA, BRAF and SMO [29].