KRAS and neoplasm: Despite some uncertainty regarding the prognostic impact of KRAS mutations due to the confounding effects of co-occurring genetic events (e.g., mutations in STK11 or KEAP1), many studies suggest a more aggressive tumor biology (frequent brain/central nervous system metastases), therapeutic resistance and poorer overall survival for affected lung cancer patients compared to those with other genotypes [7,8,9,10,42,51,52,53,54].