KRAS and non-small cell lung carcinoma: Unfortunately, the use of MEK inhibitors such as trametinib or selumetinib (alone or combined with erlotinib) resulted in limited activity in patients with KRAS-mutated NSCLC [11,12]; moreover, the dual inhibition of EGFR and MEK may lead to a secondary activation of the PI3K/AKT pathway [13] or induce MEK activation by CRAF [14].