For example, in a US study, VEGFR-1 was detected in primary CRC and hepatic metastases, but not in nonmalignant mucosa18; while, VEGFR-2 and VEGFR-3 correlated with invasive adenocarcinoma and hepatic metastasis, respectively, in Portugal CRC patients9. This evidence concerns the gene FLT4 and colorectal carcinoma.