Sentinel lymph node

Sentinel Lymph Node

The Sentinel Lymph Node (sen-ti-nel limf node) is the hypothetical first lymph node or group of nodes reached by metastasizing cancer cells from a primary tumor. The concept of the sentinel lymph node is based on the observation that cancer cells metastasize through the lymphatic system in an orderly manner, from the primary tumor to the sentinel node, then to the other nodes in the lymphatic basin.

Etymology

The term "sentinel" is derived from the Latin word "sentinella", meaning a guard or sentry. The sentinel lymph node, therefore, acts as a guard or first point of call for identifying the presence of cancer cells in the lymphatic system.

Related Terms

Lymph Node: A small bean-shaped structure that is part of the body's immune system. Lymph nodes filter substances that travel through the lymphatic fluid, and they contain lymphocytes that help the body fight infection and disease.
Tumor: An abnormal mass of tissue that results when cells divide more than they should or do not die when they should. Tumors may be benign (not cancer), or malignant (cancer).
Metastasis: The spread of cancer cells from the place where they first formed to another part of the body. In metastasis, cancer cells break away from the original (primary) tumor, travel through the blood or lymph system, and form a new tumor in other organs or tissues of the body. The new, metastatic tumor is the same type of cancer as the primary tumor.
Lymphatic System: The tissues and organs that produce, store, and carry white blood cells that fight infections and other diseases. This system includes the bone marrow, spleen, thymus, lymph nodes, and lymphatic vessels (a network of thin tubes that carry lymph and white blood cells).