NRAS and metastatic melanoma: Recent phase 3 clinical trials have advocated the usefulness of a combination of the BRAF inhibitor dabrafenib and the MEK inhibitor trametinib as first-line treatment for BRAF V600E-mutant metastatic melanomas [28, 29], as BRAF inhibitors alone cause resistance by reactivation of the MAPK pathway due to PDGFRB upregulation or NRAS mutation [30].