Why does cancer metastasize to other parts?

Generally speaking, the metastasis of cancer cells can be divided into several stages: one stage is called invasion: at this stage, cancer epithelial cells will loosen the connection between cancer liver cells, so that cancer cells can "regain their freedom" and move to other places. Bian Xiao recommended: PET/CT examination of typical cases of lung cancer (Figure) Three advantages of PET/CT examination of cancer The second stage is called infiltration: cancer cells enter the circulatory system through the endothelium of blood vessels or lymphatic vessels. The third stage is called extravasation: in this stage, survivors who have been baptized by the circulatory system will pass through the endothelial cells of microvessels and reach other tissues. The final stage is that these cancer cells migrate to the new world, thrive in other tissues and form metastatic malignant tumors. The reason why cancer cells can metastasize may be that they wake up the genes that have been sleeping for a long time in the body and are responsible for the early development of embryos, thus starting the relevant procedures, thus gaining terrible metastatic ability. In the future, it is possible to develop drugs to inhibit the expression of Twist and other genes and avoid tumor metastasis. Or by screening these genes, we can find the future trend of the tumor early and give corresponding treatment. Perhaps in the future, cancer will not be such a terrible scourge, but it may not become another chronic disease.