In order to understand about the cancer in lymph nodes, it is important to have an idea about the lymph nodes, their function and how the cancer affects them. 

What are lymph nodes?

Through nodes located all across the body, lymph veins transport lymph fluid. The lymph nodes serve as filters for foreign things like cancer cells and pathogens. They contain immune cells that can fight infection by combating and eliminating pathogens brought in by lymph fluid. Numerous areas of the body, including the neck, armpit, chest, abdomen (belly), and groin, are home to lymph node. There are two ways that cancer might affect the lymph node: it can either begin there or spread there from another location. Lymphoma is a type of cancer that develops in the lymph nodes. More frequently than not, cancer begins elsewhere and subsequently spreads to the lymph nodes.

How does cancer spread to lymph nodes?

Most cancers spread from its original location to other parts of the body. Cancer cells can spread to other organs through the lymphatic or circulatory systems when they detach from a tumor. The cancer cells may end up in lymph nodes if they circulate through the lymph system. The majority of the cancer cells that escape are killed or eliminated before they may begin to proliferate elsewhere. However, one or two of them might move, start to grow, and develop new tumors. Metastasis is the term helps to describe the cancer's spread to a new area of the body.

What is cancer in lymph nodes?

The cancer in lymph node  can also be lymphoma. However, lymphoma is not confined to the lymph node cancer alone. Lymphoma is the cancer in the bone marrow, lymph node, spleen, thymus, and other organs. Cancer in lymph nodes can be lymphoma, but lymphoma cannot be always cancer in the lymph node. 

Lymph node swelling occasionally has a connection to cancer. Some malignancies develop in lymph nodes first. Acute lymphocytic leukemia, Non-Hodgkin lymphoma, and Hodgkin lymphoma are all lymph system malignancies.

More frequently, cancer spreads from another part of the body and manifests as a metastasis in the lymph nodes. Occasionally, cancerous cells leave a tumor and spread to new areas. These cancer cells may circulate in the blood and get to other organs or they may pass through the lymphatic system and get to lymph node.

When a lymph node has cancer, a biopsy can assist in identifying the specific type of cancer present when the removed tissue or node is inspected under a microscope. Breast cancer cells in the lymphatic system will still appear to be breast cancer because the cancer cells will resemble the cancer cells of the tumor from which they came.

How to diagnose cancer in lymph nodes?

Doctors must consider additional symptoms or variables while making a diagnosis. For example, swollen lymph node close to the ear may be a sign of an ear infection. A sore throat, cough, and swollen glands in the neck region near the collarbone could all be symptoms of an upper respiratory infection. A body-wide illness that requires urgent care may be visible by several lymph node swelling.

The doctors might employ the following techniques in addition to analyzing your medical history to determine the cause of swollen lymph nodes:

To determine what is causing enlarged lymph node, clinicians may employ some of the following techniques:

Physical examination

During the physical examination, feel the nodes in the affected area with your fingertips to determine their size and whether they are firm, painful, or warm.

Lab tests 

Procedures in the lab, includes blood testing to look for any underlying diseases

Imaging tests

Ultrasonography, computed tomography (CT), magnetic resonance imaging (MRI), and X-rays are examples of imaging tests.

Biopsy

Using a biopsy, a lymph node's entirety or a part of it can be removed to be examined under a microscope.

Staging of Lymph Node Cancer

To assess the amount of cancer in the body, oncologists employ cancer staging. One of the most widely used staging techniques, TNM, heavily relies on lymph nodes. The TNM approach bases its diagnosis on the size of the tumour (T). The extent of its metastases (N), and the number of surrounding lymph node that it has infiltrated (M). Based on clinical observations, a numerical value is given to each letter. 

The N is given a value of 0 if there is no evidence of cancer in the lymph node close to the tumour. The number of nodes affected, the size and extent of the cancer, the size of the nodes, and their location are all taken into account when determining whether local or distant nodes are cancerous. The numbers of every initial are added together. The advancement of cancer  is directly proportional to the sum. That is the cancer is as advanced as the sum increases  If the TNM has a lower sum, the treatment becomes more easier. 

Treatment for lymph node cancer

Depending on the tumor's size, location, and if it has spread to other parts of the body, many treatments are available for cancer of the lymph nodes. Some types of metastatic cancer that have spread to the lymph node may be treated surgically. Chemotherapy, radiation therapy, a stem cell transplant, immunotherapy, and targeted therapy are some other possibilities for treating lymph node cancer. When cancer has progressed to lymph nodes, there is a larger chance that it may return after surgery. Following surgery in specific circumstances, chemotherapy or radiation therapy may be advised. When lymph nodes are removed, the affected area of the body may become unable to empty lymph fluid, which could result in lymphedema, a persistent issue. The likelihood of developing lymphedema increases with the amount of lymph node removed.

Conclusion

The severity of the cancer and the condition of each individual might be different. If diagnosed at an earlier stage, and with proper medication, supplements and treatments, it can attain a cure in most cases. Just like every other cancer, the cancer in lymph nodes is also serious and in case of diagnosis, seek immediate help.