What Is A Guard Node?

Cancers often lead to overuse of various procedures in the treatment of patients. Thanks to the sentinel node method, the patient is spared some steps and avoids unnecessary surgery. In this article, we will explain what a sentinel node is and how it relates to the treatment of cancer.

The sentinel node is the first lymph node to which cancer cells migrate when they detach from a parent tumor. It is not a metastasis in the broadest sense of the word, but the mechanism is similar: malignant cells move from a local tumor in one organ to other areas, and some of them arrive at a nearby lymph node.

In the case of breast cancer, the sentinel node is key in determining the degree of cancer, i.e., when considering the actual prevalence of the tumor in the body. Through a piece of sentinel node, doctors are able to predict the development of a disease in a patient.

In addition, information from the sentinel node helps to plan treatment after taking a biopsy. Based on the cancer prevalence classification, it can be decided whether only surgery, chemotherapy and radiotherapy, or some other combination of treatments are needed.

Guardian node and development of treatments

Guardian lymph node biopsy has been an important advance in the treatment of cancer. Consider that before this method, a woman with breast cancer had to undergo a huge operation in which part of the lymph node chain closest to the mother tumor was removed from her armpit.

This is not a small surgery, and  one of its most common side effects is Lymphedema,  where the lymphatic circulation is blocked. When the lymphatic circulation is blocked, fluid seeps into the soft tissues, causing swelling of the upper limb.

The removal of the entire lymph node chain had two purposes: to diagnose the prevalence of cancer and to treat any metastases already present there. The problem with this method was that  if the result of the subsequent biopsy was negative, the whole operation was done in vain  and the woman had to suffer in vain from its side effects.

The purpose of reducing the extent of surgery is to improve the quality of life of patients. Some sort of procedure is still needed, but the incision is smaller and the surgeon only removes the lymph node if the results of the biopsy indicate malignant cells there.

Guardian lymph node biopsy

A sentinel node biopsy is part of the protocol for certain breast cancers. It has been tried for melanoma, but its benefit here is still questionable.

As previously mentioned, to locate malignant cells, a sample is taken from the first lymph node to which the cancer cells would migrate from the parent tumor with the lymph. If the result is negative, the tumor is known to be localized and to remain only within that organ.

This requires a smaller incision than would be required by a large removal of the lymph node chain, but it can also have side effects. The most common of these are postoperative bleeding from the wound and inflammation in the area. However, the risk is very small.

How is a sentinel node identified?

To take a biopsy, doctors must first identify the sentinel node. This is done by utilizing methods that make that lymph node stand out from the rest. This will allow the surgeon to find the right place to perform the procedure.

One way to label a sentinel node is with radioactive material. First, the radioactive solution is injected into the areas closest to the parent tumor. This solution enters the lymphatic system and radioactivates the first lymph node in the chain.

The second method uses a blue dye. Instead of a radioactive tracer, there is a blue dye in the injection that travels the same path from the area of ​​the parent tumor to the first nearby lymph node.

The choice of the best method depends on the medical staff. Both methods are effective in locating the sentinel node and have very few side effects. The radioactive material is weak and does not cause radiation problems inside the cells. Instead, the blue dye may stain the urine bluish for some time.

What do the results of the test piece say?

After biopsy of the sentinel node, there are two ways to proceed. If the result is negative, no malignant cells were detected, i.e., no further surgery is required. The doctor will assess the patient’s condition and start appropriate treatment.

If the result is positive, the surgery will have to be extended. This means that cancer cells have been found in nearby lymph nodes and the tumor has spread.

As we always warn, early detection is important in cancers. The earlier the procedure is done, the faster the results are obtained and the better the prognosis of the disease.