Only now beginning to be understood functionally, the mutational frequency of the isoforms differs across different types of cancer; in descending order of prevalence: pancreatic adenocarcinoma (>60% KRAS), colorectal adenocarcinoma (under 40% KRAS, ~5% NRAS), lung adenocarcinoma (~30% KRAS), and skin cutaneous melanoma (~28% NRAS), among the most common cancers bearing RAS mutations [30]. This evidence concerns the gene NRAS and cancer.