KRAS and duodenal adenocarcinoma: However, among the 93 patients with duodenal adenocarcinoma, there were 23 patients with KRAS mutation, and they were significantly different from the 70 patients without KRAS mutation in terms of sex (P = 0.01), BRAF mutation (P < 0.01), and mucin phenotype (P = 0.01; Table 3).