sentinel node biopsy, biopsy of the first lymph node to receive lymphatic drainage from a malignant tumor. Also called sentinel lymph node biopsy, intraoperative lymphatic mapping. ▪ METHOD: The surgeon injects a radioactive substance and/or a blue dye near the tumor. Following injection, the agents follow the natural drainage path from the tumor to the first tier of surrounding lymph nodes. The lymph nodes most appropriate for examination then “light up” like sentinels either through the use of a device that monitors the radioactive substance or visualization of their blue stain. The first node is removed by the surgeon and examined by a pathologist. ▪ PATIENT CARE CONSIDERATIONS: Sentinel node biopsy assists in the staging of a cancer; it also serves as a mechanism to avoid extensive lymph node surgery. ▪ OUTCOME CRITERIA: A negative biopsy eliminates the need for more extensive lymph node surgery, and there is a high probability that other nodes are cancer-free. A positive biopsy assists in developing a plan for the treatment of the malignancy.
