Non-Hodgkin lymphoma (NHL) is a group of cancers of the white blood cells called lymphocytes. Lymphocytes protect the body from infection and disease. In NHL, the lymphocytes develop in the wrong way so they don’t fight infections very well. These diseased cells grow quickly and crowd out the healthy white blood cells, red blood cells and platelets that your body needs.
There are more than 30 different types of NHL that begin in the lymphocytes and spread throughout the body. In all types, diseased cells crowd out normal cells. Each type is different in how the cells grow and how the disease is treated. They are all called non-Hodgkin lymphoma to tell them apart from another cancer called Hodgkin lymphoma.
Every year, about 69,000 people are diagnosed with NHL in the United States.1 Although NHL can occur in people of any age, most people diagnosed with the disease are older than 60.1 The chances of getting NHL increases with age. For most people, the cause of NHL is unknown.
Types of NHL
There are many different types of NHL. These lymphomas are grouped based on how quickly they grow and on the kinds of lymphocytes affected.
Lymphomas that tend to grow slowly are called indolent lymphomas. Aggressive lymphomas are ones that grow quickly. They may become life-threatening within months without treatment. Sometimes, a slow growing (indolent) lymphoma can change into a more aggressive type.
Three different kinds of lymphocytes – B cells, T cells, and NK cells – can be cancerous. Most NHLs are B-cell lymphomas.
The most common types of NHL are:
- Diffuse large B-cell lymphoma – an aggressive B-cell lymphoma
- Follicular lymphoma – an indolent B-cell lymphoma
- Mantle cell lymphoma – an aggressive B-cell lymphoma
Stages of NHL
There are four stages of NHL. These stages are based on where the diseased cells are found in the body. They’re also based on how many areas of the body are affected. Lymphoma cells tend to form tumors with lymph nodes, where normal lymphocytes reside. Unlike many other cancers, even widespread (Stage 4) lymphoma is curable for many patients, though more aggressive treatment may be required. The four stages of NHL are:
Stage 1: the diseased cells are in a single lymph node group (such as in the neck or underarm)
Stage 2: the diseased cells are in more than one lymph node group but still within the upper half of the body or the lower half of the body
Stage 3: the diseased cells are in lymph nodes in both the upper and lower halves of the body
Stage 4: the diseased cells have spread to organs outside of the lymph nodes such as the liver, lungs, and bone marrow
Recurrent: the disease returns after treatment
1. Howlader N, Noone AM, Krapcho M, Garshell J, Neyman N, Altekruse SF, Kosary CL, Yu M, Ruhl J, Tatalovich Z, Cho H, Mariotto A, Lewis DR, Chen HS, Feuer EJ, Cronin KA (eds). SEER Cancer Statistics Review, 1975-2010, National Cancer Institute. Bethesda, MD, http://seer.cancer.gov/csr/1975_2010/, based on November 2012 SEER data submission, posted to the SEER web site, April 2013.