Small, bean-shaped masses of tissue scattered along the lymphatic system that act as filters and immune monitors, removing fluids, bacteria, or cancer cells that travel through the lymph system. Breast cancer cells in the lymph nodes under the arm or in the chest are a sign that the cancer has spread, and that it might recur. Lymph nodes are small glands that filter lymphatic fluid and help fight infections. They can swell due to various causes, such as infections, cancer, or autoimmune diseases. Learn more about lymph nodes and how to keep them healthy. Lymph nodes are kidney-shaped organs of the lymphatic system and the immune system, present in most parts of the body. They filter foreign particles, including cancer cells, and have a cortex, medulla and nodules with different types of cells. Lymph node, any of the small, bean-shaped masses of lymphoid tissue enclosed by a capsule of connective tissue that occur in association with the lymphatic vessels. As part of the lymphatic system, lymph nodes serve as filters for the blood, providing specialized tissues where foreign antigens can
