KRAS and colorectal carcinoma: In the primary sites, gene mutations included 13 in KRAS, 5 in NRAS, 8 in PIK3CA, and 1 in EGFR. The gene mutations in the metastatic sites were 11 in KRAS, 3 in NRAS, 6 in PIK3CA, 1 in KIT, and 1 in EGFR. No BRAF mutation was found in either the primary or the liver metastatic CRC (the details are shown in Table 3).