sentinel lymph node
The first lymph node that receives lymphatic drainage from a primary tumor site.
Full Definition
A sentinel lymph node is the initial lymph node or group of nodes that cancer cells would most likely reach first if they spread from the primary tumor through the lymphatic system. This concept is based on the orderly progression of lymphatic drainage, where cancer cells typically follow predictable pathways. Identification and biopsy of sentinel lymph nodes allows for accurate staging while minimizing the morbidity associated with extensive lymph node dissection. If sentinel nodes are negative for cancer, it suggests that downstream lymph nodes are also likely to be uninvolved.
Usage
Usage note: Often abbreviated as SLN in medical records; concept introduced by Donald Morton in melanoma surgery.
In Context
- "Sentinel lymph node biopsy was performed using blue dye and radioisotope guidance." — Operative procedure note
- "Two sentinel lymph nodes were identified and both showed micrometastases on final pathology." — Pathology report