Sentinel Lymph Node Biopsy

Sentinel lymph node is the first lymph node that drains the lymphatics from the cancer.

Sentinel Lymph Node Biopsy is a procedure in which the sentinel lymph node is identified and sent for biopsy.

One of the first questions that a patient asks the doctor when she has breast cancer is “How much has the cancer spread? ”When the cancer has not been found to have spread to the other parts of the body by clinical and as well as by investigations, Sentinel Lymph Node biopsy is done. By taking a biopsy of that node and testing whether it is affected by cancer one can know whether the cancer has spread

The Sentinel Lymph Node Biopsy is done by injecting methylene blue dye and indocyanine green dye under the nipple. By using the infrared camera, we can locate the position of the sentinel lymph node. The axilla(armpit) is opened up-to look out for the sentinel lymph node which can be identified by the colour of the dye. The lymph node is then excised and sent immediately for frozen section biopsy. By doing a fresh frozen biopsy, one can find out whether the sentinel lymph node is involved or not.

The Figure above shows the first lymph node draining the tumour in the axilla called Sentinel Lymph Node Biopsy

Sentinel Lymph Node Biopsy helps us to avoid the complications associated with Axillary Lymph Node Dissection like lymphoedema, seroma and haematoma.

Combining both Methylene blue and ICG(Indocyanine Green) to detect Sentinel Lymph Node Biopsy helps us to detect 99.5% of spread to the axillary lymph node*.

If the Sentinel Lymph node is positive, that means there has been spread to the axilla and the axilla has to be cleared of tumour by axillary lymph node dissection.

If the sentinel Lymph node biopsy is negative, it means that there has been no spread to the axilla & axillary lymph node dissection need not be done.