KRAS and neoplasm: The average percentage of liver metastasis-private mutation is higher than of primary-private mutations, this tendency was consistent to what has been previously described [8], however our data showed that liver metastasis-related signaling pathways include HGF/MET and its down-stream KRAS-MEK/ERK or PIK3CA-MTOR signaling pathway, which affect the proliferation, angiogenesis and migration of tumor cells [26, 27], not just PI3k-AKT or TGF-β signaling pathway.