Picture of Lymph Nodes

Lymph nodes, lymph, and lymphatic vessels comprise the lymphatic system of the body. Lymph nodes filter lymph, a clear, sticky fluid that bathes body cells and collects waste products and debris. Lymph also carries white blood cells, which are responsible for protecting the body against viruses and bacteria and may trap cancer cells. Lymph nodes are located throughout the body but the largest groupings are found in the neck, armpits, and groin areas. Swollen lymph nodes may be a sign that the body is dealing with an infection, injury, or cancer.