NCIt definition : A technique that uses dyes and/or radioactive agents to map the lymphatic drainage
of an area in which a tumor is located, thereby identifying the sentinel node.;
Alternative definition : NCI-GLOSS: The use of dyes and radioactive substances to identify the first lymph
node to which cancer is likely to spread from the primary tumor. Cancer cells may
appear first in the sentinel node before spreading to other lymph nodes and other
places in the body.;