KRAS and neoplasm: While, to date, MEK inhibitors have conventionally been used in combination with BRAF inhibitors to reinforce the blockade of the MAP kinase (MAPK) growth signaling pathway in BRAF V600E-mutant cancers (including BTCs in the ROAR basket trial [48]), the rationale, in this case, is to use MAPK blockade for immune modulation in addition to the suppression of tumor growth, regardless of BRAF or KRAS mutational status.