Sentinel Lymph Node Biopsy (SLNB)

You have early stage breast cancer, and the lymph nodes in your underarm do not appear to have cancer.
The first few lymph nodes (sentinel lymph nodes, SLN) in your underarm where the lymphatic vessels from the breast drain to, will be removed and examined during surgery under the microscope (frozen section).
This is done under GA (asleep) and it is to determine if cancer has spread to these SLN.
A blue dye or a radioactive substance is injected around the cancer site or at the nipple prior to surgery to locate the SLN.
- The radioactive substance will be injected before the operation in the Department of Nuclear Medicine.
- The blue dye will be injected during the operation.
If cancer is detected in the SLN, lymph nodes in the axilla are removed. If no cancer is detected in the SLN, no further surgery is needed.
The final histology will be reviewed about 1 week after surgery.
In 2 - 3% of cases, the final assessment of the SLN may be different from the initial frozen section result and a second operation may be required.
If the dye or radioactive substance is not able to identify the SLN, we will have to proceed to perform an axillary clearance.