how does cancer spread or metastasize
If the cells travel through the lymph system, they may end up in nearby lymph nodes (small, bean-sized collections of immune cells) or they may spread to other organs. More often, cancer cells that break off from the main tumor travel through the bloodstream. Once in the blood, they can go to any part of the body.Many of these cells die, but some may settle in a new area, begin to grow, and form new tumors. This spread of cancer to a new part of the body is called metastasis.Cancer cells have to go through several steps to spread to new parts of the body:. 1  They have to be able to break away from the original tumor and enter the bloodstream or lymph system, which can carry them to another part of the body.he liver is a common site of spread for cancer cells that start in the colon because blood from the intestines flows into the liver. Cancer cells often break away from the main (primary) tumor and travel through the blood and/or lymph system, but they donât always settle in and start new tumors.