Sentinel lymph node biopsy (SLNB) is a procedure to check whether breast cancer has spread to the lymph nodes in the armpit. Instead of removing many nodes, the surgeon finds and removes the first one to three nodes that drain the breast, called sentinel nodes. If these are free of cancer, the rest are usually left alone, which lowers the risk of arm swelling (lymphedema).
Why Are Lymph Nodes Checked?
Lymph nodes are often the first place breast cancer spreads. Knowing whether nodes are involved helps:
- Stage the cancer accurately
- Decide on chemotherapy, radiation or hormone treatment
- Plan further surgery if needed
How Is SLNB Done?
- A blue dye, a radioactive tracer or both are injected near the tumour or nipple
- The tracer travels to the sentinel nodes
- During surgery, the surgeon locates the coloured or radioactive nodes
- One to three nodes are usually removed through a small cut in the armpit
- Nodes are examined by a pathologist
It is often done at the same time as lumpectomy or mastectomy.
SLNB vs Axillary Lymph Node Dissection
- SLNB: removes a few nodes, lower risk of lymphedema, quicker recovery
- Axillary dissection: removes many nodes, higher risk of arm swelling and stiffness, used when nodes are clearly involved
Who Is Suitable for SLNB?
- Early breast cancer
- No obviously enlarged or cancerous nodes on exam or imaging
- Some patients after chemotherapy, depending on response
What Are the Risks?
- Mild pain or numbness in the armpit
- Temporary blue discolouration of skin or urine from the dye
- Rare allergic reaction to dye
- Small risk of lymphedema, much lower than with full dissection
- Fluid collection (seroma)
Recovery
- Most people return to light activities within days
- Gentle arm exercises help prevent stiffness
- Watch for swelling, redness or fever
Key Takeaways
- SLNB removes only the first few nodes.
- It accurately stages most early breast cancers.
- It lowers the risk of lymphedema.
- Dye or tracer helps find the nodes.
- Results guide further treatment.
Final Thoughts
Sentinel node biopsy is a major advance that spares many women from extensive armpit surgery. Understanding it can ease anxiety before your operation. For breast cancer surgery planning, you can consult Dr. Varadharajan, a surgical oncologist in Chennai.
