How is the lymphatic system involved in metastasis?

Metastasis, the spread of cancer from one site to another within the body, is mediated through the lymphatic system. The lymphatic vasculature is a network of vessels that transports clear fluid throughout the body. This fluid carries white blood cells and other immune cells which are integral in helping fight infection and disease. Metastases can occur when cancer cells break away from tumors, circulate in this lymphatic fluid, then attach to other tissues or organs where they begin to proliferate.

The most common sites for metastases include bone marrow, lungs, liver and sometimes even distant parts of the body like brain or skin. This process begins with tumor cells forming protrusions called podosomes on their surface that allow them to attach themselves on blood vessel walls and migrate along it’s flow into new tissues or organs. Once at its destination the tumor cell follows an extravasation step where it escapes from within a blood or lymph vessel into nearby tissue; here on out those same podosomes help guide further invasion by degrading matrix proteins around them aiding movement between healthy tissue until eventually reaching it new home inside a secondary organ or tumor niche proving favorable for colonization resulting in further metastasis growth formation later on down line as underlying mechanisms come together contributing all sorts advanced factors associated with inflammatory microenvironment control leading up towards first metastatic event itself .