Lymphoma is the most common type of blood cancer in the United States. It is the seventh most common cancer in adults and the third most common in children. Lymphoma is a cancer that develops in the lymphatic system (or lymph system) which gives us our immunity. Our body has cells called lymphocytes which are white blood cells. Lymphocytes are our infection-fighting immune cells. These cells are present in lymph nodes, spleen, thymus, bone marrow, tonsils and adenoids, and other parts of the body. When you have lymphoma, lymphocytes change and grow out of control. Lymphoma is characterized by formation of solid tumors in the immune system. While there are dozens of subtypes of lymphoma, the two main types are non-Hodgkin’s lymphoma (approximately 90% of cases) and Hodgkin’s lymphoma (approximately 10% of cases). Non-Hodgkin’s and Hodgkin’s lymphoma each affect a different type of lymphocyte. Every type of lymphoma grows at a different rate and responds differently to treatment.
While some risk factors for developing lymphoma have been identified, the exact cause remains a mystery. The main symptom is usually an enlargement of lymph nodes in some part of the body. If the enlargement of lymph nodes is from infection, it subsides once the infection clears, but if the enlargement of lymph nodes is from lymphoma, it does not go away. When a doctor suspects lymphoma from a patient’s history, they will rule out other problems by ordering some tests. A confirmed diagnosis of lymphoma requires a biopsy (removal of tissue from the body for laboratory analysis). Analysis of the biopsy sample helps determine the type and stage of lymphoma if one is present. Because lymphoid tissue is present in many parts of the body, lymphoma can originate almost anywhere. Most often it starts in lymph nodes in the upper part of the body. The most common sites are in the chest, neck, or under the arms. Lymphoma most often spreads through the lymph vessels in a graded fashion from lymph node to lymph node. Rarely, at an advanced stage of the disease, it can invade the bloodstream and spread to distant parts of the body, including the liver, lungs, and bone marrow.
Even though lymphoma is cancer, it is treatable, and many cases can even be cured. Your doctor can help you find the right treatment for your type of lymphoma. You cannot do anything to prevent lymphoma, but with modern medical treatments, survival rates are good. Treatments for lymphoma are similar to other cancers and include chemotherapy, radiation therapy, and specialized drug therapy. It may also be possible to treat lymphoma with stem cell transplantation following standard therapy.
Lymphoma is different from leukemia. Each of these cancers starts in a different type of cell. Lymphoma starts in infection-fighting lymphocytes. Leukemia starts in blood-forming cells inside the bone marrow. Lymphoma is also not the same as lymphedema, which is a collection of fluid that forms under the skin when lymph nodes are damaged.
FACTS AND FIGURES:
- The incidence of lymphoma varies by geographical region. The areas with the highest incidence are North America, Europe, and Australasia.
- There are more than 750,000 people living with, or in remission from, lymphoma in the United States alone.
- An estimated 70,000 people will be diagnosed with lymphoma in 2015 in the United States.
- The five-year survival rate has doubled from 40% in 1963 to 70%-80% in 2010.
- Approximately 2% of men and women will be diagnosed with non-Hodgkin’s lymphoma at some point during their lifetime.
- Non-Hodgkin’s lymphoma is among the top 10 most common types of cancers and represents approximately 4% of all new cancer cases in the United States.
- Non-Hodgkin’s lymphoma is more common in men than women, and more common in people of Caucasian descent.
- The average age at diagnosis is 66 years old.