Blood cancer: Lymphoma

Types of lymphomas

There are three main types of blood cancers - leukaemias, lymphomas and myeloma.

Lymphomas are a group of blood cancers that start in the glands (lymph nodes) and organs of the lymphatic system. The lymphatic system is part of your immune system (1,2): a network of channels, organs and glands (lymph nodes) that runs throughout your body.

Blood cells called lymphocytes begin to grow out of control and can collect in the lymph nodes, spleen and thymus gland (1,2). Some leukaemias are also cancers of lymphocytes (1). The main difference is that in leukaemias, the cancerous cells are circulating in the blood, rather than collecting in the lymph nodes and lymphatic organs (1).

There are two main groups of lymphomas:

• non-Hodgkin’s lymphoma (NHL)
• Hodgkin’s lymphoma.

There are also many different types of non-Hodgkin’s lymphoma (1). It’s important to find out from your doctor which type of lymphoma you have. Your doctor will choose the best treatment for you depending on the type.

Non-Hodgkin's lymphoma

There are two main types of non-Hodgkin’s lymphoma (NHL): B cell and T cell lymphomas (3). The most common type of NHL is diffuse large B cell lymphoma (DLBCL) (1). Other types of lymphoma affecting B cells are follicular lymphoma and mantle cell lymphoma (3).

As well as being grouped by type of cell, lymphomas are grouped according to whether they are slow-growing or fast-growing (3):

• DLBCL and mantle cell are generally fast-growing (‘high grade’) lymphomas (3)
• Follicular lymphoma is a slow-growing (low-grade) lymphoma (3).

Diffuse Large B Cell lymphoma

Diffuse large B cell lymphoma (DLBCL) is a fast-growing type of NHL (3,4). There are many different subtypes (3,5). In all of them, white blood cells called B lymphocytes have become cancerous (3). These cells are part of the immune system and grow in glands (lymph nodes) and the spleen (1,3). However, they can also collect in body tissues outside the lymphatic system (4). It is called ‘diffuse’ because under a microscope the cells look spread out, rather than clumped together (4).

We do not know what causes most cases of DLBCL. Lymphomas become more common as you get older (6). Most people are over 65 when they are diagnosed with DLBCL (7). Risk factors include lowered immunity, for example, an autoimmune condition, HIV or taking immune-suppressing medicines after an organ transplant (7).

Symptoms

The main symptom of DLBCL is swollen glands (lymph nodes), most often in the neck, armpit or groin (8). These are usually painless and can come up quite quickly, within weeks.

Some people also (8,9):

• feel very tired
• have fevers and sweating at night
• lose weight
• lose their appetite
• feel full or uncomfortable because of a swollen liver or spleen
• have severe itching.

You may have other symptoms that depend on where else the lymphoma is growing. For example, DLBCL that is growing in the stomach or bowel can cause diarrhoea. If it is in the chest, it can cause a cough or breathlessness (8).

Treatment

DLBCL is most often treated using a combination of chemotherapy and immunotherapy drugs called R-CHOP(10). You have cycles of treatment every three weeks (10). The number of cycles you have depends on how far the DLBCL had developed when you were diagnosed (11). If you have advanced DLBCL, you may have a different combination of chemotherapy drugs (11). Some people have radiotherapy as well, usually because they have very enlarged, bulky lymph nodes (10,11).

If you still have signs of DLBCL after your treatment (partial remission), or if it comes back later, you can have more chemo-immunotherapy (10). If you are fit enough, you may then have a stem cell transplant using your own blood stem cells, rather than from a donor (10). This is called an autologous transplant.

CAR-T cell therapy is another treatment option for adults whose DLBCL has come back after two different types of treatment (12).

Outlook (prognosis)

The aim of DLBCL treatment is to try to cure it (10).

Many people have complete remission after treatment. Overall, around seven out of 10 people diagnosed with early-stage DLBCL live for five years or more. Around five out of 10 people diagnosed with advanced-stage DLBCL live for five years or more (14).

These figures do not mean people only live for five years. They relate to the number of people who are still alive five years after their diagnosis. Patients who take part in clinical trials usually have their health monitored for five years after treatment, so ‘five-year survival’ is a commonly quoted statistic.

Mantle cell lymphoma (MCL)

Mantle cell is usually a type of fast-growing lymphoma. But some people have a slow-growing type. In MCL, white blood cells called B lymphocytes have become cancerous. It is named after an area inside lymph nodes called the ‘mantle zone’, where this type of lymphoma grows (15). The cancerous B lymphocytes can collect in lymph nodes, the bone marrow, spleen and other body organs (16).

We do not know what causes mantle cell lymphoma (17). It is quite rare and more often diagnosed in middle-aged or older men (17). Most people have a particular gene change (mutation) in the B lymphocytes, but we do not know why it happens (17).

Symptoms

The main symptom of MCL is painless, swollen glands (lymph nodes), most often in the neck, armpit or groin (16).

You may also:

• feel full or uncomfortable because of a swollen spleen (18).
• feel very tired
• have fevers and sweating at night
• lose weight
• itch for no reason (16)).

If MCL is in your bone marrow, it can cause (18):

• anaemia, because of low red blood cell levels
• bruising, bleeding or a rash of blood spots under the skin, caused by low platelets. Platelets help the blood to clot
• frequent infections because of low white cell levels.

Treatment

MCL treatment depends on your test results, the type you have, how far it is grown and your general health and fitness. Most people have advanced fast-growing MCL when they are diagnosed (19). Treatment is usually a combination of chemotherapy and immunotherapy drugs. If you are fit enough, you may then have a stem cell transplant using your own blood stem cells, rather than from a donor (16,19): an autologous transplant.

After your treatment, your doctor may suggest maintenance treatment to try and stop or delay the MCL coming back. This is usually a two-monthly injection of an immunotherapy drug called rituximab (19).

If you have early MCL when diagnosed, you may just have radiotherapy to the area containing the MCL. If you have the slow-growing type of MCL, with no troublesome symptoms, your doctor may just monitor you and keep treatment in reserve (19).

There is another treatment option for adults whose MCL has not responded or has come back after treatment with a targeted treatment (12). It is called CAR-T cell therapy. There is more about this in the page on types of treatment.

Outlook

The outlook for MCL is very variable. If you have the slow-growing type, you may not need treatment for months or even years (20).

With the fast-growing type, treatment is usually successful at getting rid of the MCL. But unfortunately it nearly always comes back within months or years and needs more treatment (20).

It is very difficult to put together accurate statistics for a condition that is so rare and varies so much in type and treatment. Only about 75 people are diagnosed with MCL in the UK each year (21). So it is best to ask your own specialist as they have all the information on your case and treatment.

Generally, patients who are able to have more intensive treatment do better (22). On average, looking at all situations, people with MCL live for around three to five years (21,22). But in one research study looking at patients who had a stem cell transplant, half the patients were still living 12 years after their treatment . Remember that figures are always looking at past results, and treatments for MCL have improved in recent years (22).

Follicular lymphoma

This is the most common type of slow-growing lymphoma (23). White blood cells called B lymphocytes become cancerous. They grow in lymph nodes in clumps, called follicles (24). In some people, follicular lymphoma can transform into a more aggressive type. If it does, this may be many years later (25).

We do not know what causes follicular lymphoma. It is most often diagnosed in people over 60 (23).

Symptoms

The main symptom of follicular lymphoma is painless, swollen glands (lymph nodes), most often in the neck, armpit or groin (25). If you have follicular lymphoma, you may:

• have fevers and sweating at night (25)
• lose weight (26)
• feel very tired (26).

Some people also have itching and frequent infections that are difficult to get rid of (25,26).

Treatment

Follicular lymphoma treatment depends on your test results, how much it is grown, your symptoms, and your general health and fitness (26). If the disease is at an early stage and is only in one part of your body, you may have radiotherapy (27). This can sometimes cure it completely (25).

If you have no symptoms and radiotherapy isn’t suitable, your doctor may just monitor your condition and keep treatment in reserve (25,27).

Most people are diagnosed with more advanced follicular lymphoma. Treatment is usually chemotherapy and immunotherapy. If you have no symptoms, your doctor may monitor you and keep treatment back until you do.

If your lymphoma disappears after treatment (complete remission) your doctor may suggest maintenance treatment to delay it coming back. This is usually a two-monthly injection of an immunotherapy drug called Rituximab.

If follicular lymphoma comes back, you may have more chemotherapy or immunotherapy to get it back into remission (25). If you are fit enough, you may have more intensive chemotherapy with a stem cell transplant (25).

Very rarely, follicular lymphoma can change into a faster-growing type of lymphoma (28). Doctors call this ‘transformation’. If your lymphoma transforms (1), you are likely to have more chemotherapy, and if that helps, may also have a stem cell transplant (25). The transplant is usually using your own blood stem cells - an autologous transplant, but in rare cases, you may have a transplant with donor cells: an allogeneic transplant (29,30). This is more likely if you are relatively young and fit (30).

Outlook

Because it is such a slow-growing disease, people usually live for many years with follicular lymphoma (25). If it is diagnosed when it is at an early stage, some people may be cured (25). Even with advanced disease, around eight out of 10 people live for five years or more after diagnosis (31).

This figure doesn’t mean people only live for five years. It relates to the number of people who are still alive five years after their diagnosis. Patients who take part in clinical trials usually have their health monitored for five years after treatment, so ‘five-year survival’ is a commonly quoted statistic.

Hodgkin’s lymphoma

Another type of lymphoma, Hodgkin’s lymphoma also develops from B cells (32). It is most often diagnosed either in young people, in their early 20s or in people over 70 (33).

We do not know exactly what causes Hodgkin’s lymphoma(34). There are likely to be multiple factors working together. It is linked to an infection with the virus that causes glandular fever, but not in all cases (34). In around one in 20 cases there is family history of Hodgkin’s lymphoma (34).

Symptoms

The main symptom of Hodgkin’s lymphoma is (usually) painless, swollen glands (lymph nodes), most often in the neck or just above the collarbone. Less often, they are in the armpit or groin (35). Some people also:

• have fevers and sweating at night
• lose weight
• have cough, chest pain or difficulty breathing if lymph nodes in the chest are affected
• have general or localised itching.

Treatment

Hodgkin’s lymphoma treatment mainly depends on how far the disease has grown when you are diagnosed. The main treatment is chemotherapy, with or without radiotherapy. If the Hodgkin’s lymphoma doesn’t respond to treatment or comes back, your doctor may suggest a stem cell transplant with your own blood stem cells, an autologous transplant. In very rare cases, if the disease comes back again, you may have a stem cell transplant using cells from a donor - an allogeneic transplant (36).

Outlook

The aim of treatment for Hodgkin’s lymphoma is to try to cure it (36). The disease can be controlled long-term in nine out of 10 people with early disease and many of them will have been cured. Even with advanced disease, treatment can control it in between six and eight out of 10 people (37,38). Some of these people will also have been cured (38).