Sentinel node biopsy is a surgical procedure in which the sentinel nodes are removed. It is performed to test for cancer or determine its stage. The sentinel nodes are the lymph nodes that are usually the first to be affected by the spread of cancer cells.
Lymph nodes play an important role in the body’s immune response to foreign substances and disease. They are part of the lymphatic system, a system of organs and vessels through which lymph flows. The lymph fluid and lymph nodes contain important immune system fighter cells.
A sentinel node biopsy is a surgical procedure performed to check for cancer. In this procedure, the sentinel nodes are surgically removed. They are then examined and tested to check for cancer cells.
Sentinel nodes are the first lymph nodes that cancer cells start to affect when they enter the lymphatic system. The procedure is also known as a sentinel lymph node biopsy (SLNB) or SLNB procedure.
Sentinel node biopsy is important because many cancers spread through the lymphatic system. The lymph nodes are spread through the body and linked by vessels and are usually the first to be affected.
The sentinel lymph node biopsy (SLNB) checks whether cancer has spread from a cancerous tumour into the lymph nodes.
A doctor performs an SLNB procedure to determine the stage that cancer has reached.
Certain cancers usually start by spreading to the sentinel nodes. Determining the stage of cancer or how much it has advanced can help the doctor suggest the appropriate treatment.
The doctor may perform the SLNB procedure when removing the original cancer tumour but may also do it before or after.
Sentinel node biopsy is used for certain types of cancer to check whether the cancer has spread. It is most commonly used for breast cancer and melanoma – a kind of skin cancer.
However, the SLNB procedure is also used for other types of cancer. These include the following:
- Colon, gastric, stomach, rectal, or oesophagal cancer (cancers of the digestive system)
- Penile cancer (cancer of the penis)
- Endometrial cancer (cancer of the uterus)
- Vulvar and cervical cancer (cancer of the vulva and cervix in women)
- Cancer of the neck and head
- Non-small cell lung cancer (one of the main types of lung cancer)
Before the sentinel node biopsy procedure, a radioactive trace substance is injected into your vein. This tracer helps the surgeon find the sentinel lymph node during the SLNB procedure. A blue dye may also be used since it stains the sentinel nodes blue.
During the SLNB procedure, you receive general anaesthesia to put you to sleep. The surgeon cuts a small part of the skin and looks for the blue dye or the radioactive tracer to locate the sentinel node. The radioactive substance is located with a gamma detector.
During the SLNB procedure, the surgeon may take out between one to five sentinel nodes. The incision is then closed and sealed with surgical tape, stitches (sutures), or surgical glue.
After the SLNB procedure, the sentinel nodes are sent to a lab to test for cancer cells.
SLNB benefits mainly relate to diagnosing cancer and determining the stage of cancer. Sentinel node biopsy helps the doctor diagnose and understand the stage of cancer and how far it has progressed.
Sentinel node biopsy negative result
A negative result in a sentinel node biopsy usually indicates that cancer has not spread to the lymph nodes or other organs. If the sentinel nodes test negative for cancer, you will not need further testing of your lymph nodes.
If the sentinel node tests negative for cancer, the removal has the benefit of preventing the spread of cancer through the lymph nodes and avoiding more extensive surgery of lymph nodes.
Sentinel node biopsy positive result
A positive result in a sentinel node biopsy indicates that cancer has entered the lymph nodes and may spread to other lymph nodes through the lymphatic system. A sentinel node biopsy can show whether the cancer cells are likely to spread to other body parts.
However, if the sentinel nodes test positive, there is a risk that more lymph nodes may be affected by the cancer cells. Your doctor may suggest removing more lymph nodes after or along with the sentinel node biopsy.
The sentinel lymph node biopsy (SLNB) is usually a safe procedure. However, there are certain risks and potential complications associated with the SLNB procedure. The risk factors of the SLNB procedure may include the following:
These include bleeding, swelling, redness, pain, bruising, or infection at the spot of the incision.
An allergic reaction to the dye used to stain the sentinel nodes may occur in rare cases.
Lymphedema is one of the main sentinel lymph node biopsy complications. It refers to swelling caused by a buildup of excess lymph fluid.
During the surgery, lymph vessels connecting to the sentinel node are cut. This disrupts the flow of lymph fluid, leading to an abnormal buildup.
Along with swelling in the body’s tissues, lymphedema may also cause discomfort or pain.
Regular screening and testing for cancer are important to diagnose it and start treatment as soon as possible. If you are concerned that you have cancer or have been diagnosed with cancer, you may need to undergo a sentinel node biopsy. Based on the test results, our oncologist can suggest appropriate treatment and measures to prevent the spread of cancer.
We offer comprehensive diagnostics to assess risks and detect and treat cancer. We offer high-precision surgical intervention for gynaecological, breast, gastrointestinal cancers, and other tumours. We have state-of-the-art chemo daycare and precision medicine, and multidisciplinary care.
Book an appointment with Dr Neha Sharma at CK Birla Hospital for the best consultation and treatment.