Sentinel lymph node biopsy: areas of application

Thanks to modern technologies, many malignant tumors are diagnosed at an early stage, which significantly increases the chances of a complete cure for cancer patients and their return to a full-fledged healthy life.

 

Unfortunately, finding the tumor itself does not mean making a definitive diagnosis. To begin treatment, it is necessary to make sure that there are no metastases – the spread of tumor cells to other organs and tissues. Cells can enter other organs with blood – this is hematogenous metastasis. In addition, the spread occurs with the flow of lymph – lymphogenic metastasis, with the lymph nodes being the first to be affected.

 

Currently, oncologists have in their arsenal a large number of diagnostic methods for detecting metastases in lymph nodes and organs – ultrasound, CT, MRI, PET. However, none of these methods can detect micrometastases in lymph nodes, which usually begin the process of metastasis. That is why many patients with identified malignant neoplasms undergo preventive lymph dissection – removal of all lymph nodes in the path of lymph outflow from the tumor. Such operations require a lot of time, have many complications, and often lead to disability of patients. Statistics show that in most cases, in the early stages of cancer, lymph dissection was performed in vain, since micrometastases are not found in the removed lymph nodes.

 

In order to avoid such complications, reduce and secure surgical intervention, in the early stages of breast cancer and skin melanoma, a sentinel lymph node biopsy is recommended by international standards.

 

The sentinel lymph node is the first lymph node on the path of lymph outflow from the tumor. In the absence of damage to the sentinel lymph node by metastases of any size (micrometastases, macrometastases), all other lymph nodes in this lymph drainage basin are considered intact, that is, healthy, and there is no need to remove them, as well as to diagnose them.

 

To examine the sentinel lymph node, it is necessary to remove it (perform a biopsy of the sentinel lymph node). This is a minimally invasive procedure, the purpose of which is to determine the extent of cancer and avoid advanced lymph dissection.

 

Determining the location of the sentinel lymph node is the most important preparatory stage for a biopsy. The most widespread and effective method is isotope labeling using lymphoscintigraphy, which is performed immediately before surgery or the day before it.