KRAS and non-small cell lung carcinoma: The strongest proof of KRAS being a negative prognostic factor in NSCLC was reported by Mascaux et al. who conducted a meta-analysis of 53 studies and found that KRAS mutation correlated with a significantly worse prognosis (hazard ratio [HR] 1.40; p = 0.01; HR 1.5 for LADCs; p = 0.02) [33].