Question: When is a sentinel node biopsy considered, and when is an axillary lymph node dissection necessary?
Answer: Whenever a woman is diagnosed with breast cancer, it's important for us to stage the patient, the woman, accurately. Part of this staging requires an assessment of the lymph nodes under the armpit.
For women who have noninvasive breast cancer, what we call DCIS, we do not generally recommend assessment of the lymph nodes. There are some specific incidences when we might, but as a general rule we don't. If a woman is diagnosed with invasive breast cancer, it is important to check the lymph nodes and at this point in time the standard of care would recommend a sentinel lymph node biopsy.
If, when we check a woman we see that the lymph nodes under the armpit are swollen, or we clinically feel that there may be enlargement of the lymph nodes, we would not recommend sentinel lymph node biopsy, but rather axillary lymph node dissection, meaning taking many of the lymph nodes from the armpit.
If we operate on a woman and perform a sentinel lymph node biopsy and any of the lymph nodes show tumor, the typical discussion you would then have with your surgeon is whether or not you need to go back in and perform what we call a completion axillary dissection, which would be to remove the rest of the lymph nodes in the armpit.