What is Lymph Node Cancer?
Cancer in the lymph nodes is known as lymph node cancer. The cancer can either start primarily in the lymph nodes themselves or can spread (metastasis) from some other primary tumor from other part of the body to the lymph nodes.
Before we learn more about what is lymph node cancer and its causes, symptoms, treatment and recovery period, let us know more about lymph node, its function, causes of lymph node swelling.
What are Lymph Nodes?
Lymph nodes are the glands or organs, which are small in size and are shaped like beans and produce and store the blood cells, which help in fighting disease and infection. Lymph nodes also eliminate the fluids and cell waste from the lymphatic fluid (lymph), and store the white blood cells (lymphocytes). Lymph nodes are a part of the lymphatic system and are present throughout the body, including the armpits, neck, abdomen and groin.
The Lymph System
There is a network of lymph nodes and lymph vessels present in our body, which form a part of our immune system. Its function is to filter fluid, waste material, and organisms such as bacteria and viruses, which are present in the tissues of the body. Lymph vessels are similar to veins where instead of carrying blood, the lymph vessels carry lymph, which is a clear and watery fluid. This lymph fluid oozes from the capillary walls and washes over the tissue cells of the body. The lymph carries oxygen along with other nutrients to the cells and also carries away waste products, such as carbon dioxide (CO2) which exits the cells. The white blood cells present in the lymph fluid helps in fighting infections. If the lymph fluid does not get drained properly, then it starts to accumulate and results in swelling of the lymph nodes. The role of the lymph vessels is to carry and drain the lymph fluid by drawing the lymph fluid around the cells and carrying it towards the chest where it gets collected into a large vessel, which then drains into a blood vessel present close to the heart.
Function of Lymph Nodes
The lymph vessels direct the lymph fluid through the lymph nodes situated all over the body. Lymph nodes are small glands, which act as filters for harmful substances which are present in the lymph vessels which reach them. Lymph nodes also have immune cells, which help in fighting infection by destroying germs, which are present in the lymph fluid. The lymph fluid flowing from the fingers travels towards the chest and joins the lymph fluid from the arm. This lymph fluid can get filtered through the lymph nodes present under the arm or present in the elbow. The lymph fluid from the scalp, head and face travels down through the lymph nodes present in the neck.
The lymph nodes, which are situated deep in the body, such as around the bowels and between the lungs, filter the lymph fluid present in those regions. The lymph fluid gradually flows in from all over the body and travels back to the chest.
Causes of Lymph Node Swelling & What it Indicates
There are various causes for lymph node swelling. The most common cause is infection (viral, bacteria, fungal). In some cases, the swelling in the lymph node can be due to some other underlying medical condition. When the swelling in lymph node persists and is associated with other symptoms, such as weight loss, fever or night sweats with no other sign of infection, then it imperative to seek immediate medical evaluation.
When a body suffers from any problem, such as injury, infection or cancer; then the lymph nodes in that region increase in size or swell, as they have to work more to filter out the harmful cells. This results in lymphadenopathy, which are enlarged or swollen lymph nodes. Swelling in the lymph nodes indicates that something is wrong in the body. Other associated symptoms help in diagnosing what exactly is wrong in the body. These symptoms can be fever, ear ache, pain etc. Swollen lymph nodes near the ear can indicate that there is an ear infection or cold.
Common areas where swelling of the lymph nodes occurs are: the neck, underarms and groin. In most of the cases, there is swelling in only one area of lymph nodes at a time. When there is swelling in more than one area of the lymph nodes, then it is known as generalized lymphadenopathy. Certain medicines, some infections (chicken pox, strep throat), immune system diseases, and cancers, such as leukemia and lymphoma can cause such type of swelling.
For diagnosis of the cause of lymph node swelling, detailed medical history of the patient is taken along with other lab investigations.
Cancer in the Lymph Node
Cancer can be one of the cause which results in swelling of the lymph nodes. There are 2 methods in which the cancer can appear in the lymph nodes. Cancer can either originate in the lymph nodes (lymphoma) or can spread to the lymph nodes from some other part of the body, which is more common. Swelling and pain in the region of the lymph nodes is one of the common cancer symptoms, which originate in the lymphatic system. Some of these cancers include Hodgkin lymphoma and non-Hodgkin lymphoma. Cancer can originate in another region of the body and metastasize to the lymph nodes. The cancer is called after the region of the body where it started even after it has spread to the lymph nodes.
The cancer cells break away from the tumor and travel to other regions of the body through the lymph system or the bloodstream. The cancer cells travel through the bloodstream and spread to the distant organs. If the cancer cells travel by the lymph system, then they spread to the lymph nodes. Many of the cancer cells are killed or die before they spread and grow someplace else. But a few of them may settle in a new region and grow resulting in formation of new tumors. This spreading of cancer to new areas of the body is known as metastasis.
When the cancer reaches and starts to grow inside the lymph nodes, it often affects the lymph nodes, which are present close to the primary tumor. These lymph nodes do most of the work of filtering or killing the cancer cells.
Causes of Lymph Node Cancer
The exact cause of any cancer including lymph node cancer is not known. The cause of the cancer is thought to be changes in the cells of the DNA, which causes rapid and uncontrollable division of the cells where instead of the cell stopping in its growth and dying, continue to divide and grow, leading to accumulation of the cells resulting in tumor or cancer.
Some of the factors which increase the risk of lymph node cancer or any other cancer include: patient's age, gender, ethnicity, family history, diet, environmental exposure etc.
Signs & Symptoms of Lymph Node Cancer
- Swelling of the affected lymph nodes which can be painless initially. Pain will follow later
- Swelling in the legs or ankles
- Bloating and cramping in the abdomen.
- Night sweats.
- Loss of appetite and unintentional weight loss.
- Tiredness, fatigue and lack of energy.
- Altered sensation.
- Persistent coughing.
- Enlarged tonsils.
Role of Lymph Nodes in Cancer Staging
Lymph nodes play a vital role in finding out the cancer stage and also help in determining the extent or the amount of the cancer present in the body. The TNM system is one of the most commonly used systems for cancer staging and is based on the extent of the tumor (T), the degree to which the cancer has spread to the lymph nodes (N), and if there is any metastasis present (M).
If the lymph nodes near the cancer site have no cancer in them then the N in the TNM is given a value of 0. If the adjacent or distant lymph nodes have cancer, then the N is given a number of 1, 2 or 3, according to the number or lymph nodes affected, the size and location of the lymph nodes and the extent of cancer in them.
Meaning of Cancer in the Lymph Node
If the number of cancer cells present in the lymph node is less then special tests are done for detecting them. If there are very few cancer cells in a lymph node, then the treatment plan may remain the same. However, if there is lot of cancer in a lymph node, then the tumor can be easily seen. If the growth of the cancer extends out of the lymph node through the connective tissue layer, then it is known as extracapsular extension. If there are lot of cancer cells in the lymph nodes, then it means that the cancer is fast growing and the likelihood of it spreading or metastasizing to other places in the body is more. But if the cancer is found only in the adjacent lymph nodes other than the primary site, then the entire cancer can be removed by removing the main tumor and the lymph nodes which are present. Cancer which has spread to distant lymph nodes from the primary cancer site will likely need additional treatment other than surgery, such as chemotherapy and radiation.
How the Lymph Node Cancer Affects the Cancer Stage?
Treatment of cancer is decided after finding out the type of the cancer and the stage of the cancer the patient has. As mentioned before, the TNM system is the most common staging system of cancer. A cancer which has less TNM numbers is often easy to treat with a better prognosis. A cancer with higher TNM numbers is difficult to treat and has a poor prognosis.
Removal of Lymph Nodes in lymph node cancer during surgery leaves a part of the body which doesn't have any means to drain off the lymph fluid in the affected region. The lymph vessels end up on a dead end where previously a lymph node was present, leading to backing up and accumulation of lymph fluid. This results in lymphedema, which can become a life-long problem and the severity of which depends on the number of lymph nodes which are removed.
Diagnosis of Lymph Node Cancer
The diagnosis of lymph node cancer can be made doing the following:
- Medical history and Physical examination of the patient.
- Blood and urine tests.
- Biopsy of the involved lymph node.
- Imaging tests such as x-ray, ultrasound, PET scan, CT scan and MRI scan help in visualizing the lymph nodes more clearly.
- Nuclear medicine scans such as bone scans.
- Genomic testing
- Genetic tests.
Normally, the lymph nodes in our body are tiny and are usually hard to feel, however, when there is any problem such as injury, inflammation, infection or cancer, then the lymph nodes increase in their size. Those lymph nodes which are present near the surface of the body can get big enough to be felt by the fingers and some can even be visible. However, if the number of cancer cells present in a lymph node is less, then the lymph node may look and feel normal. In such cases, cancer must be checked by removing a part or all of the lymph node.
During surgery for removing primary cancer, one or more than one of the regional or adjacent lymph nodes may need to be removed. When one lymph node is removed, then it is known as biopsy. If many lymph nodes are removed, then it is known as lymph node dissection or lymph node sampling. If cancer has metastasized to the lymph nodes, then the risk of relapse of cancer after the surgery increases. Depending on the metastasis, the oncologist will decide what additional treatment needs to be done like radiation and chemotherapy after the surgery.
Needle biopsy is done on the enlarged lymph nodes. The tissue sample, which is removed is sent to the lab and is looked under the microscope to detect cancer cells.
Other imaging tests and scans are also done to look for enlarged lymph nodes which are present deep in the body. Commonly the enlarged lymph nodes present near the cancer contain cancer.
Treatment for Lymph Node Cancer
- Treatment for lymph node cancer depends on different aspects, such as the size and location of the tumor, the degree of cancer in the lymph nodes, the stage of the cancer and the spreading or metastasis of the cancer to other parts of the body.
- Surgery is done to remove the cancer and the lymph nodes, which have cancer in them, are also removed. If the primary site of cancer is the lymph node, then the entire lymph node is removed. If the cancer has spread to the lymph nodes from other sites, then a part or complete lymph node is removed.
- Chemotherapy and radiation therapy are also done depending on the type and size of the lymph node cancer. Chemotherapy consists of drugs, which are used to kill the cancer cells. Chemotherapy can be given before surgery to try and reduce the size of the tumor and can also be given after the surgery to kill of any remaining cancer cells.
- Similarly, radiation therapy can also be given before the surgery for reducing the size of the tumor and can be given after the surgery to destroy any cancer cells which have remained after the surgery. Radiation therapy comprises of powerful x-ray beams which are targeted on the area of the cancer/tumor to kill the cancer cells.
- Stem cell transplantation and bone marrow transplantation are other treatment options for lymph node cancer.
Prognosis & Life Expectancy in Lymph Node Cancer
The life expectancy of a patient suffering from lymph node cancer is usually measured from the time of diagnosis and helps in determining the most effective treatment for the cancer which will also help in preventing relapse of the cancer. Any recurrence of the cancer in the lymph node can cause serious health complications, and if not detected and treated on time, can be fatal. The survival rate of the lymph node cancer is an important factor in determining the capacity of the patient in fighting the cancer. The prognosis and life expectancy of the patient suffering from lymph node cancer depends on certain factors, such as patient's age, medical history, type of cancer and stage of the cancer. Prognosis and life expectancy in lymph node cancer is better if the patient has a strong immune system and if the cancer is detected and treated at the right time. The younger the patient is, the better the prognosis of the patient is; as with age, the tissues become weak and the resistance of the body to infections also decreases along with the response to treatment of the cancer also tends to diminish with age. Thus, the chances of stopping the growth of the cancer decreases, and the spreading and recurrence of cancer increase with age.
The prognosis and life expectancy of the patient also greatly depends on the stage of the cancer. The prognosis is good in the initial stages of lymph node cancer and is poor in advanced stages.
The medical history of the patient is one of the important determining factors in determining the survival rate and life expectancy of the patient. If the patient has recurrent cancer in the lymph nodes, then they have a very low survival rate with a poor prognosis.
The prognosis of lymph node cancer increases if the cancer is detected on time and appropriate treatment is started.