What is non-Hodgkin lymphoma?
Non-Hodgkin lymphoma (NHL) is any lymphoma that is not Hodgkin lymphoma. Hodgkin lymphomas contain abnormal cells called ‘Reed–Sternberg cells’. NHL is any lymphoma that does not contain this type of cell.
Lymphoma occurs when a lymphocyte (a type of white blood cell) becomes out of control. There are 2 types of lymphocytes: B lymphocytes (B cells) and T lymphocytes (T cells). There are many different types of NHL. They can be classified by the type of lymphocyte they develop from, either B-cell lymphomas (majority) or T-cell lymphomas.
NHLs are also classified by how they behave. Some types grow slowly (low-grade lymphomas) and others grow at a faster rate (high-grade lymphomas).
Sometimes a lymphoma changes from a slow-growing type into a faster-growing type. This is known as ‘transformation’. The transformed lymphoma has to then be treated as a high-grade lymphoma.
Who gets non-Hodgkin lymphoma?
More than 13,000 people are diagnosed with NHL each year in the UK. In addition, more than 3,000 people each year are diagnosed with chronic lymphocytic leukaemia (CLL), which is sometimes considered a form of NHL. NHL is more common than Hodgkin lymphoma – nearly 2,000 people are diagnosed with Hodgkin lymphoma each year in the UK.
The risk of developing NHL increases with age. Most people who are diagnosed are over 55. It affects slightly more men than women.
Types of non-Hodgkin lymphoma
Below is an overview of the types of NHL. If you have been told you have a less common type of lymphoma that we do not mention, please contact our helpline for advice on where to find information most suitable to your needs.
We have more information about these types of lymphoma as separate pages on our website. Most are also described in our booklets on high-grade or low-grade NHL.
NHL is called ‘high grade’ when the cells appear to be dividing quickly. Some types of high-grade NHL grow faster than others. You may hear high-grade types of NHL called ‘aggressive’ lymphomas. This might sound alarming, but people with high-grade lymphomas are often more likely to be treated successfully and stay in remission (no evidence of lymphoma) than people with low-grade lymphomas.
The risk of developing high-grade NHL increases with age. Most people diagnosed with these types of lymphoma are over 50. However, high-grade NHL can occur at any age, including in children. Some types of non-Hodgkin lymphoma occur mostly in children and young people. These tend to be high-grade lymphomas.
Your prognosis (outlook) depends on many factors, including what type of lymphoma you have, its stage, and your general health. However, many types of high-grade NHL respond well to treatment. Most people with high-grade NHL go into remission (no evidence of lymphoma) and stay in remission for a long time.
High-grade NHL can be B-cell or T-cell lymphoma. There are many different types of high-grade NHL.
- diffuse large B-cell lymphoma (DLBCL) – the most common type of NHL. There are also some rare sub-types of large cell lymphoma like
- Burkitt lymphoma – the most common type of NHL in children and young people
- mantle cell lymphoma
- primary central nervous system lymphoma (primary CNS lymphoma).
T-cell non-Hodgkin lymphomas
- peripheral T-cell lymphoma not otherwise specified (PTCL-NOS)
- anaplastic large cell lymphoma (ALCL)
- angioimmunoblastic T-cell lymphoma (AITL)
- enteropathy-associated T-cell lymphoma (EATL)
- adult T-cell leukaemia/lymphoma (ATLL)
- extranodal NK/T-cell lymphoma (nasal-type)
- hepatosplenic T-cell lymphoma
- lymphoblastic lymphoma (usually T-cell but can be a B-cell lymphoma).
Non-Hodgkin lymphoma is called ‘low grade’ or ‘indolent’ when the lymphoma cells are dividing slowly. Low-grade non-Hodgkin lymphoma can develop over a long period of time.
When your lymphoma is diagnosed, you have tests that help your doctors work out how much of your body is affected by lymphoma and where the lymphoma is (staging).
Most people have advanced-stage low-grade NHL by the time they are diagnosed. Early-stage low-grade NHL – usually stage 1 and rarely stage 2 – may be successfully treated and stay in remission for a long time.
Advanced-stage low-grade NHLs – usually stage 3 and 4 – are difficult to cure. They are chronic (long-lasting), flaring up and needing treatment from time-to-time. This is sometimes known as a ‘relapsing and remitting’ course as you may have periods when your lymphoma is in remission and periods when it relapses (comes back) and needs more treatment. Some people don’t need treatment for low-grade NHL straightaway but are monitored until treatment is needed. This approach is called active monitoring or watch and wait.
Doctors aim to control advanced-stage low-grade NHL, rather than cure it. People with low-grade NHL often go for long periods when they feel well and don’t need treatment.
Low-grade NHLs are more common as you get older and are very rare in children and young adults.
There are many different types of low-grade NHL, including:
- follicular lymphoma – the most common type of low-grade NHL
- chronic lymphocytic leukaemia (CLL)/small lymphocytic lymphoma (SLL)
- lymphoplasmacytic lymphoma (Waldenström’s macroglobulinaemia)
- marginal zone lymphomas:
- hairy cell leukaemia.
Most skin lymphomas are low-grade NHLs.