Definition
A sentinel lymph node, also known as sentinel lymph node, is the lymph node that is located in the first place in a lymph drainage area of a tumor. When tumor cells spread via the lymphatic path, the first thing that happens is that these cells metastasize to the sentinel lymph node. If this lymph node is therefore not affected, it can be assumed with a high degree of probability that there are no further metastases or that the tumor has not yet spread. The sentinel lymph node plays an important role, especially in breast cancer and malignant skin cancer.
Anatomy
Lymph nodes are distributed throughout our body. A distinction is made between regional lymph nodes and collective lymph nodes: regional lymph nodes receive lymph directly from the organs and collective lymph nodes receive lymph from several regional lymph nodes. The sentinel lymph node is the first lymph node in the drainage area of a tumor.
Depending on where the tumor is located, the sentinel lymph node may be located elsewhere in the body. There are many lymph nodes around the breast, especially near the armpits. If the tumor sits on the side of the breast, the sentinel lymph node is located slightly above towards the armpit.
It is the first lymph node that is affected by metastasis of breast cancer via the lymphatic pathway, since it is directly connected to the tumor via a lymph vessel. However, this small lymph node is not in the same place in every woman and can be difficult to find. To identify the sentinel lymph node, one can administer colored solution or radioactive substances, which can then be seen by means of the staining or with the help of a radiation detector.
Lymph nodes are usually up to one centimeter in size. The size can vary depending on the activity status. Lymph nodes can swell up painfully when they have to protect the body against foreign bodies, for example when you have a cold. Lymph nodes can also be enlarged if malignant changes occur. In this case, however, they are usually not painful and are difficult to move against the surrounding tissue.
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