The first step in sentinel lymph node biopsy is injecting a dye or radioactive tracer liquid (or both) into the nipple area. If you're awake during the procedure, this injection can be painful.

Does sentinel node dye injection hurt?

Sentinel lymph node biopsy (SLNB) has been reliably accurate as a minimally invasive surgical alternative for identifying lymphatic breast metastasis. During mapping, the injection of a radioactive tracer or isosulfan blue dye to differentiate the SLN is acutely painful.

How long does a sentinel node injection take?

While you're in the reclining chair, a doctor or nurse will inject a small amount of a radioactive liquid under your skin below the areola of your affected breast. You might feel stinging or burning during the injection. After the injection, you will massage the area of the injection site for 10 minutes.