When comparing the mutational gene status between the primary site of CRC with lung and liver metastasis (the details are shown in Table 3), we found that there was no significant difference in KRAS, NRAS, BRAF, and PIK3CA. Regarding the metastatic site, gene mutations in the lung metastatic sites were significantly much more prevalent than those in the liver metastatic sites (p = 0.000), with a total 26 gene mutations (26/30, 86.7%) and 22 gene mutations (22/50, 44%), respectively. This evidence concerns the gene PIK3CA and colorectal carcinoma.