Lymphoma is a broad term for a type of cancer that targets your body’s lymph system. It starts in the white blood cells (lymphocytes) that are part of your body’s immune system. Lymphoma is divided into two main types: Hodgkin’s lymphoma and non-Hodgkin lymphoma (NHL). In this article, we’ll discuss the many types of NHL.
The Lymphatic System
The lymphatic system is similar to the circulatory system that moves blood around the body. Instead of pushing blood through the system, the lymphatic system moves lymphatic fluid through lymph nodes and vessels to remove waste from the body.
There are hundreds of lymph nodes spread throughout the body. When cancer is found in the lymph nodes, there are two possible ways that it appeared here. The first is that the cancer started, or originated there. The second is that cancer spread to the lymph nodes from somewhere else. Cancer that started in the lymph nodes is called lymphoma. Lymphomas can affect the tissues in your lymphatic system.
Lymph tissue is located in your:
- Spleen, which makes white blood and immune system cells, and filters out damaged cells, bacteria, and cell waste
- Bone marrow is the tissue inside certain bones that makes new blood cells
- Thymus, which is important in developing T-lymphocytes
- Tonsils and adenoids are collections of lymph tissue that make antibodies against germs
- Stomach and intestines
Non-Hodgkin Lymphoma Classifications
NHL is classified as one of three major types:
- B-cell lymphoma, the most common type of lymphoma in the United States, comprising about 90% of cases
- T-cell lymphoma only occurs in about 10% of cases
- NK-cell lymphoma occurs in less than 1% of lymphoma cases
NHL is also classified according to how fast it’s growing: “indolent” if growth is normal, or “aggressive” if it’s growing rapidly.
Indolent or low-grade, NHL tends to grow slowly, with few symptoms. Patients may not need treatment right away. They can be monitored regularly, waiting to start treatment until symptoms develop or the NHL starts to change. It’s rather common for indolent lymphomas to become aggressive over time.
Radiation therapy can treat indolent NHL if it’s diagnosed early, in stage I or II because it’s localized in one area of the body. Most NHL cases are stage III or IV by the time they are diagnosed.
Aggressive, also referred to as intermediate- or high-grade lymphoma, grows and spreads rapidly, usually causing severe symptoms. Treatment will start immediately and requires intensive chemotherapy. Chemotherapy is a treatment that is able to treat the entire body because it is injected into the bloodstream. Lymphomas are typically highly susceptible to chemotherapy treatment. Radiation therapy may be added to treat NHLs that are stage I or stage II or if the lymphoma is large. Some types of aggressive lymphoma can be cured with effective treatment.
Sub-types of NHL
There are more than 60 types of NHL, although some are very rare. The most common types are diffuse large B-cell lymphoma and follicular lymphoma. While lymphoma can start in either B or T cells, B-cell lymphoma is most common.
It’s important for your doctor to determine what NHL subtype you have. Each type has different behavior and requires different treatment. Diagnosis is made by looking at the lymphoma tissue under a microscope and with other tests.
- Diffuse large B-cell lymphoma (DLBCL) comprises about 30% of NHL cases in the United States. It is more common in older people, often starting as a fast-growing mass in a lymph node or organs other than the lymph system. Although it is aggressive, chemotherapy and radiation therapy (if the NHL is in a limited area) are used successfully in about 75% of patients.
- Follicular lymphoma is the second most common type of lymphoma, comprising about 20% of NHL cases. The average age at diagnosis is 60 years; it is very rare in young people. Usually beginning in the lymph nodes, it can also be in the bone marrow. It is indolent, and in most cases, grows very slowly. Over time, it can turn into DLBCL and will need more aggressive treatment that’s used with DLBCL.
- Mantle cell lymphoma occurs in about 7% of NHL cases. Most cases happen to men over age 60. This type of cancer involves the lymph nodes, bone marrow, spleen, esophagus, stomach, and intestines. Patients with the slower-growing form without symptoms may only need regular monitoring. This is usually the case with older patients.
- Small lymphocytic lymphoma, comprising about 5% of all NHL cases, is an indolent type. It’s the same as B-cell chronic lymphocytic leukemia without significant disease in the blood system. Some patients only require regular monitoring; others receive chemotherapy and targeted therapy with a monoclonal antibody or other drugs.
- Double hit/triple hit lymphoma is highly aggressive and accounts for about 5% of cases. Both of these lymphomas are a result of gene changes. Most cases occur in older adults. Very rarely, indolent follicular lymphoma can transform into double-hit lymphoma.
- Primary mediastinal large B-cell lymphoma is an aggressive form of DLBCL. It presents as a large mass in the chest. The mass can cause breathing problems or partial blockage of the major vein that carries blood from the upper body and arms to the heart. Chemotherapy and drugs are the most common treatments. Radiation is used when chemotherapy is not effective.
- Splenic marginal zone B-cell lymphoma begins in the spleen and usually involves bone marrow and blood. A slow-growing NHL, it is treated with regular monitoring. If treatment is needed, it can include drugs, chemotherapy, or surgery to remove the spleen.
- Extranodal marginal zone B-cell lymphoma, also known as mucosa-associated lymphoid tissue lymphoma, most often occurs in the stomach. It can also occur on the skin, in the lung, thyroid, salivary gland, eye, or bowel.
- Nodal marginal zone B-cell lymphoma is an indolent lymphoma targeting the lymph nodes. It is rare, comprising only 1% of lymphoma cases. It is treated like follicular lymphoma.
- Lymphoplasmacytic lymphoma is a rare indolent lymphoma, affecting 1% of people with NHL. It involves the bone marrow, spleen, and sometimes lymph nodes. Most cases (90%) are due to gene changes. Treatment can include regular monitoring, chemotherapy, and targeted monoclonal antibodies therapy.
- Primary effusion lymphoma is a rare and very aggressive form of lymphoma. It is more common in people who have HIV/AIDS, an impaired immune system, or who are elderly. It usually presents as fluid build-up around the heart, lungs, or abdominal area.
Subtypes of T-cell and NK-cell lymphoma include:
- Anaplastic large-cell lymphoma, the primary cutaneous type, is usually indolent and only involves the skin. More common in young people or children, it can also occur in older adults. Although it is fast-growing, cure rates are good.
- Anaplastic large cell lymphoma, systemic type, comprises about 2% of all lymphomas but about 10% of all childhood lymphomas. It is an aggressive lymphoma, and chemotherapy is usually an effective treatment.
- T-lymphoblastic lymphoma/leukemia is rare (1% of cases) and is most common in teens or young adults, especially males. It often starts in the thymus (where many T-cells are made).
- Breast implant-associated anaplastic large cell lymphoma is a recently recognized subtype that occurs near breast implants. Treatment includes the removal of the implants.
- Peripheral T-cell lymphoma, not otherwise specified (NOA), is an aggressive form that’s often advanced by the time it’s diagnosed. Most common in older people, it comprises about 6% of all lymphomas.
- Angioimmunoblastic T-cell lymphoma is an aggressive lymphoma that accounts for about 4% of all lymphomas. More common in older people. Symptoms include enlarged lymph nodes, fever, weight loss, rash, and frequent infections.
- Adult T-cell lymphoma/leukemia is an aggressive lymphoma caused by a virus that involves bone and skin. Bone marrow transplantation seems to be the best treatment.
- Hepatosplenic T-cell lymphoma is an aggressive form of lymphoma that involves the liver and spleen. It most often occurs in teenagers and young males. It can be managed with chemotherapy followed by bone marrow transplantation.
- Subcutaneous panniculitis-like T-cell lymphoma involves tissue under the skin and is treated as high-risk aggressive lymphoma.
- Enteropathy-associated intestinal T-cell lymphoma occurs in the lining of the intestines. Symptoms include severe stomach pain, nausea, vomiting, and intestinal bleeding. More common in men than women, this lymphoma occurs in some people with celiac disease.
At Willamette Valley Cancer Institute, our hematologists understand how to care for patients with various types of lymphoma. Learn more about lymphoma treatment options.