Lymph Node Metastatic Carcinoma at 10x Magnification

The lymph nodes are part of the lymphatic system and function primarily in filtering out and destroying foreign substances in the blood. While this role of the lymph nodes is invaluable to the body’s fight against infection, it can actually facilitate the spread of cancer. Lymph nodes located near a primary tumor, referred to as regional lymph nodes, are often the depositories of any cancer cells that are able to break away from the original growth. The cells usually enter the lymphatic system through the lymphatic vessels, which drain and concentrate their materials in the lymph nodes. Cancer cells sometimes begin growing in the lymph nodes, but they may also escape the nodes and then travel to even more distant parts of the body, where they can become lodged and initiate secondary tumor growth. The other principal means of distributing cancer cells of a primary tumor to other organs or areas is via the circulatory system.