Lymphoma

Lymphoma is a cancer of the lymphatic system. There are two main types: non-Hodgkin lymphoma (NHL) and Hodgkin lymphoma. The two are told apart by how the cancer cells look under a microscope. In some ways they are similar, but the treatment for each is different.

Non-Hodgkin lymphoma is one of the more common cancers. It can occur in children but is more common in adults. Hodgkin lymphoma is much less common.

The lymphatic system#

The lymphatic system is part of the immune system, which helps protect the body against infection. It is made up of lymph nodes connected by lymph vessels, which branch out into all parts of the body except the brain and spinal cord. It also includes the bone marrow, spleen, thymus gland and tonsils.

Its main jobs are to fight infection, to drain fluid from body tissues back into the bloodstream, and to filter the blood and lymph. The system carries a clear fluid called lymph, which contains white blood cells called lymphocytes. Lymphocytes mature within the blood and bone marrow and are stored in the lymph nodes. Lymph nodes are found in many areas of the body, including the neck, armpits, chest, abdomen and groin.

As lymphatic fluid is filtered through the lymph nodes, foreign organisms such as bacteria are trapped and attacked by the lymphocytes.

A person with lymphoma has a large number of abnormal lymphocytes. These do not work properly and replace some of the normal lymphocytes, which can affect how the body fights infection. A build-up of abnormal lymphocytes causes enlarged, painless lymph nodes.

Where lymphoma can occur#

Because the lymphatic system runs through most of the body, lymphoma can develop almost anywhere. It is most commonly first seen in the lymph nodes of the neck, but it is also often found in the liver or spleen. It may also occur in the bowel, stomach, brain, skin, testicles and eyes.

Symptoms#

The most common symptom of lymphoma is swelling of the lymph nodes in the neck, armpit or groin. These enlarged lymph nodes are usually painless.

Other general symptoms can include:

• unexplained weight loss (more than one-tenth of your total weight)
• fever that comes and goes without any obvious cause
• heavy sweating, especially at night
• unexplained itching of the skin

Doctors call fever, night sweats and weight loss “B symptoms”. Some people with lymphoma have them, but many do not. Sometimes lymphoma gets into the bone marrow, causing problems with low blood counts.

Most people who have these symptoms will not have lymphoma — they are usually caused by a much less serious problem, such as an infection. Even so, it is always important to see your doctor if you have persistent symptoms.

Causes and risk factors#

We do not know why most people develop lymphoma. Because there are many different types, it is unlikely that there is a single cause. Some known or possible risk factors include:

• certain viral infections, including the human immunodeficiency virus (HIV)
• the Epstein-Barr virus, particularly in people whose immune system is suppressed
• exposure to high levels of radiation
• exposure to certain chemicals over long periods of time

Other risk factors are still being researched.

Diagnosis#

At a general examination, your doctor will ask about your symptoms and check for swelling in your lymph nodes, usually in the neck, armpits and groin. If lymphoma is suspected, further tests will be arranged. These may include:

• physical examination and blood tests
• lymph node biopsy – a small amount of tissue is removed from a swollen lymph node and examined under a microscope
• chest x-rays
• computed tomography (CT) scan – a specialised x-ray that builds up three-dimensional pictures of the body
• gallium scan – a short-acting radioactive gallium is injected to outline organs during the scan, helping to identify infection, inflammation and tumours
• positron emission tomography (PET) scan – a small amount of radioactive material is injected, which highlights cancerous areas when viewed with a special scanner
• bone marrow biopsy – a small sample of bone marrow is taken from the hip bone and examined under a microscope for cancer cells

Test results can take a few days to a week to come back. It is natural to feel anxious while waiting. It can help to talk to a close friend or relative about how you are feeling, or to speak with an experienced cancer nurse through a cancer support service.

Staging#

Lymphoma is “staged” according to its location and spread, which helps determine the type of treatment needed. The stages are:

• Stage I – cancer is found in one lymph node area, or in one area or organ outside the lymph nodes.
• Stage II – cancer is found in two or more lymph node areas, or in one area or organ outside the lymph nodes, on the same side of the diaphragm (the sheet of muscle beneath the lungs that enables breathing).
• Stage III – cancer is found in lymph node areas on both sides of the diaphragm.
• Stage IV – cancer has spread outside the lymphatic system to one or more organs, such as the spleen, liver or skin.

Treatment#

Treatment depends on the location and severity of the cancer, and differs between Hodgkin and non-Hodgkin lymphoma. Treatment for Hodgkin lymphoma is often very successful, with many people being cured. Non-Hodgkin lymphoma is also curable, but can be harder to treat. Some people need only one treatment, while others need a combination. Options include:

• Watch and wait – some slow-growing forms of non-Hodgkin lymphoma may not need active treatment when first diagnosed. Regular check-ups will be necessary.
• Chemotherapy – medication that destroys or slows the growth of fast-growing cancer cells, given as tablets or injections, usually as a combination of drugs over several courses.
• Radiotherapy – x-rays used to target and kill cancer cells. This is used in adults but rarely used to treat children with lymphoma.
• Steroids – tablets or injections that can improve how well chemotherapy works.
• Targeted therapies (immunotherapy and monoclonal antibodies) – immunotherapy, sometimes called biologic therapy, uses part of your immune system to fight blood cancer cells. Monoclonal antibodies are a type of immunotherapy that attach to specific cancer cells, signalling the immune system to destroy them and helping to slow cancer cell growth.
• Stem cell (or bone marrow) transplantation – stem cells are the cells that blood cells develop from. A transplant allows much higher doses of chemotherapy than usual, which can improve the chances of cure or prolong remission. The high doses, sometimes given with total body irradiation (TBI), destroy the bone marrow and stem cells. Afterwards you are given an infusion of either your own stem cells (autologous transplant) or stem cells from a donor (allogeneic transplant). An autologous transplant may be suggested if the lymphoma comes back or does not respond to first treatment. Allogeneic transplants have more side effects and complications and are not suitable for everyone.
• CAR T-cell therapy – a type of immunotherapy and gene therapy in which some of your own T-cells (immune cells) are genetically changed so they recognise proteins on the surface of cancer cells and attempt to kill them.
• Supportive care – prevents and treats symptoms; examples include blood and platelet transfusions.

For more detail on any of these treatments, ask your doctor or a cancer support organisation.

Complementary therapies#

When used alongside conventional cancer treatment, some complementary therapies can make you feel better and improve your quality of life. Others may not help, and in some cases may be harmful. Always discuss any complementary or alternative therapy with your medical team before starting it.

Side effects#

All treatments have side effects, which vary depending on the type of treatment. Many are temporary, but some may be permanent. Your doctor will explain the possible side effects before treatment begins.

Sexuality, relationships and wellbeing#

Lymphoma and its treatment can affect the way you feel about your body, who you are, your relationships, the way you express yourself sexually, and your sexual feelings. These changes can be very upsetting. Your medical team should discuss these issues with you before and during treatment. If you would like to talk further, ask your doctor for a referral to a counsellor. If you have a partner, it helps to be as open as possible with them about how you are feeling.

Research, caring and advanced disease#

Early detection and better treatment have improved survival for people with lymphoma, and research is ongoing.

Caring for someone with cancer can be a difficult and emotional time. If you or someone you know is caring for a person with lymphoma, support is available.

If lymphoma is diagnosed in its later stages, the cancer may have spread to the point where a cure is no longer possible. Treatment then focuses on improving quality of life by relieving symptoms — this is called palliative treatment. Medications can be used to relieve pain, nausea and vomiting.

Key points#

• Non-Hodgkin lymphoma and Hodgkin lymphoma are similar in some ways, but the treatment for each is different.
• Lymphoma can occur in children but is more common in adults.
• Hodgkin lymphoma is much less common than non-Hodgkin lymphoma.
• The lymphatic system’s main job is to help fight infection.
• A build-up of abnormal lymphocytes causes enlarged, painless lymph nodes.

Where to get help#