VEGFA and metastatic malignant neoplasm: Bevacizumab takes vascular endothelial growth factor as a target, reduces neovascularization, promotes the degradation of the existing tumor blood vessels, blocks oxygen, blood and other nutrients for tumor growth, inhibits endothelial cell mitosis, leads the surviving tumor blood vessels to tend to be normal, limits the growth of tumors, and has obvious effects on the treatment of various metastatic cancers.