Hodgkin's lymphoma is cancer of the B lymphocytes (a type of white blood cell) found in the lymphatic system, which is a network of vessels and glands spread throughout your body.
The lymphatic system is part of your immune system. Clear fluid called lymph flows through the lymphatic vessels and contains infection-fighting white blood cells known as lymphocytes.
In lymphoma, these lymphocytes start to multiply in an abnormal way and begin to collect in certain parts of the lymphatic system, such as the lymph nodes (glands). The affected lymphocytes lose their infection-fighting properties, making you more vulnerable to infection.
The most common symptom of Hodgkin's lymphoma is a painless swelling in a lymph node, usually in the neck, armpit or groin. Read more about the symptoms of Hodgkin's lymphoma.
Who is affected
Hodgkin's lymphoma mostly affects young adults aged between 15 and 35 and adults over the age of 50. More men than women are affected.
Nearly 1,500 people are diagnosed with Hodgkin's lymphoma in the UK each year.
What causes it?
The cause of Hodgkin's lymphoma is unknown. Risk factors for developing it include having a medical condition that weakens your immune system, taking immunosuppressant medication and being previously exposed to the Epstein-Barr virus (which causes glandular fever). Read more information about the causes of Hodgkin's lymphoma.
Diagnosing Hodgkin's lymphoma
The only way to confirm a diagnosis of Hodgkin's lymphoma is by carrying out a biopsy (testing a sample of affected lymph node tissue). Read more information about diagnosing Hodgkin's lymphoma.
Treatment and outlook
Hodgkin's lymphoma is a relatively aggressive cancer and can quickly spread through the body. Despite this, it is also one of the most easily treated types of cancer.
Almost all young people with Hodgkin's lymphoma will be fully cured. For older people over the age of 50, the cure rate is around 75%-80%.
Your recommended treatment plan will depend on your general health and age, because many of the treatments can cause serious side effects and complications, which can put a tremendous strain on the body. Treatments include chemotherapy, radiotherapy and steroid therapy. Read more about the treatment of Hodgkin's lymphoma.
The most common symptom of Hodgkin’s lymphoma is a painless swelling in a lymph node, usually in the neck, armpit or groin.
The swelling is caused by an excess of affected lymphocytes (white blood cells) collecting in your lymph node.
Some people may find that the swelling aches. Swollen nodes or glands are a common response to infection, so if you have swollen nodes don't panic; it is highly unlikely they are the result of lymphoma. Read more information about lumps and swellings.
Other symptoms will usually only begin once the cancer has spread through most or all of your lymphatic system.
This causes the lymphatic system to stop working properly, which weakens your immune response.
Symptoms of advanced Hodgkin's lymphoma include:
- unexplained tiredness or fatigue
- night sweats
- unexplained weight loss
- trouble getting rid of infections or increased risk of infection
- a persistent cough or feeling of breathlessness
- persistent itching of the skin all over the body
Other symptoms will depend on where in the body the enlarged lymph glands are. For example, if the lymphoma is in the abdomen (tummy), you may have abdominal pain or indigestion.
A few people with Hodgkin’s lymphoma have abnormal cells in their bone marrow when they are diagnosed. This can reduce the number of healthy cells in the blood and cause some of the above symptoms, as well as excessive bleeding, such as nosebleeds, heavy periods and spots of blood under the skin.
In rare cases, people with Hodgkin’s lymphoma may have pain in their affected lymph gland when they drink alcohol.
Lymphoma begins with a change to the structure of DNA in the B lymphocytes (type of white blood cell).
This DNA change is known as a genetic mutation.
The DNA gives the cells a basic set of instructions, such as when to grow and reproduce.The mutation in the DNA changes these instructions so that the cells keep growing. This causes them to multiply uncontrollably.
The abnormal lymphocyte cells usually begin to multiply in one or more lymph nodes in a particular area of the body, such as your neck or groin. Over time, it is possible for the abnormal lymphocyte cells to spread into other parts of your body, such as your bone marrow, spleen, liver, skin and lungs.
What triggers lymphoma?
The cause of the initial mutation that triggers lymphoma is unknown. Some experts believe it could be due to a number of related causes.
The known risk factors for developing lymphoma are:
- having a medical condition that weakens your immune system, such as HIV (this is known as immunosuppression)
- having medical treatment that weakens your immune system; for example, taking immunosuppressants because you have received an organ transplant
- being previously exposed to the Epstein-Barr virus (EBV), which slightly increases your chance of developing lymphoma (EBV is a common virus that causes glandular fever, although most people develop immunity to it)
- having received chemotherapy or radiotherapy for an earlier unrelated cancer; this slightly increases your risk of developing lymphoma
Hodgkin's lymphoma is not infectious and does not run in families. But there is a slightly higher chance of developing the condition if you have an identical twin with the cancer.
Swollen lymph nodes and other associated symptoms can suggest a diagnosis of lymphoma, but the only way to confirm the diagnosis is by carrying out a biopsy.
A biopsy involves removing some or all of an affected lymph node, which is then studied in a laboratory. Biopsies can be carried out under a local anaesthetic (where the area is numbed), although there may be some cases where the affected lymph node is not easily accessible and a general anaesthetic may be required (you are put to sleep).
A pathologist (expert in the study of diseased tissue) will then check the tissue sample for the presence of cancerous cells. If they find cancerous cells, they can also identify exactly which type of lymphoma you have, which is an important factor in planning your treatment.
Confirming a diagnosis
There are two main types of lymphocytes (white blood cells found in lymph):
- B-lymphocytes make antibodies that attack infecting bacteria and viruses
- T-lymphocytes kill cells that have been infected with a virus and cause the immune response to respond faster to an infection the second time round
In Hodgkin’s lymphoma, a cell called the Reed-Sternberg cell (a B-lymphocyte that has become cancerous) is usually present.
If a biopsy reveals the presence of Hodgkin's lymphoma, further testing will be required to check how far the lymphoma has spread. This allows a doctor to diagnose at what stage your lymphoma might be.
Further tests may include:
- Blood tests – samples of blood will be taken throughout your diagnosis and treatment to check your general health, the levels of red and white cells and platelets in your blood, and how well organs, such as your liver and kidney, are working.
- Bone marrow sample – another biopsy may be carried out to see if the lymphoma has spread to your bone marrow. This involves using a long needle to remove a sample of bone marrow from your pelvis and can be done using a local anaesthetic.
- Chest X-ray – this can check whether your lymphoma has spread to your chest or lungs.
- Computerised tomography (CT) scan – takes a series of X-rays that build up a 3-D picture of the inside of the body to check the spread of your lymphoma.
- Magnetic resonance imaging (MRI) scan – uses strong magnetic fields instead of X-rays to build up a detailed picture of areas of your body to check the spread of your lymphoma.
- Positron emission tomography (PET) scan – a type of scan that shows how the tissues of the body are working by measuring the activity of cells in different parts of the body. It can check the spread of your lymphoma and the impact of treatment.
- Lumbar puncture – using a thin needle, a sample of spinal fluid is taken and examined to see if it contains any lymphoma cells.
Staging of lymphoma
When the testing is complete, it should be possible to determine the stage of your lymphoma. These stages are explained below.
- Stage 1: the lymphoma is limited to one group of lymph nodes, such as your neck or groin nodes either above or below your diaphragm.
- Stage 2: two or more lymph node groups are affected either above or below the diaphragm.
- Stage 3: the lymphoma has now spread to lymph node groups above and below the diaphragm.
- Stage 4: the lymphoma has spread through the lymphatic system and is now present in organs or bone marrow outside of the lymphatic system.
Sometimes, health professionals use an additional grading system, either "A" or "B".
- A-type lymphoma means that you have no additional symptoms other than swollen lymph nodes.
- B-type lymphoma means that you have additional symptoms, such as weight loss, fever or night sweats.
Your treatment plan will depend on your general health and your age, because many of the treatments can cause serious side effects and complications, which can put a tremendous strain on the body.
It is likely that discussion about your treatment plan will take place with several doctors and other health professionals who specialise in different aspects of treating lymphoma.
Your care team will recommend the best treatment options to you. However, you should not be rushed into making a decision about your treatment plan. Before deciding, you may wish to talk to friends, family and your partner.
Chemotherapy is a widely used treatment for lymphoma, often combined with radiotherapy. The type of chemotherapy you receive will depend on the stage of your Hodgkin's lymphoma.
If it is thought that your lymphoma is curable, you will normally receive an intensive treatment programe of chemotherapy injections (intravenous chemotherapy), designed to kill all of the cancerous cells in your body. However, if a cure is unlikely, a more moderate treatment programme involving taking chemotherapy tablets may be used, which can often provide long-term relief from symptoms.
Chemotherapy is usually given over a period of a few months on an outpatient basis, which means you should not have to stay in hospital overnight. But there may be times when your symptoms or the side effects of treatment become particularly troublesome, and a longer hospital stay may be needed.
Chemotherapy kills the cancerous cells but it can also damage healthy cells, which can lead to several common side effects. These include:
- loss of appetite
- mouth ulcers
- skin rashes
- hair loss
- infertility: this may be temporary or permanent
The side effects should pass once your treatment has finished. However, tell your care team if the side effects become particularly troublesome, as there are medicines that can help you cope better with some side effects. For example, creams and gels can treat mouth ulcers.
Read more about chemotherapy.
Intensive chemotherapy can also damage your bone marrow. This can interfere with the production of healthy blood cells, which can lead to the following symptoms:
- increased vulnerability to infection
- bleeding and bruising more easily
Treatment may need to be delayed so that you can produce more healthy blood cells. Growth factor medicines can also stimulate the production of blood cells.
If the damage to the bone marrow is extensive, you may require a stem cell transplant to replace the damaged bone marrow.
Radiotherapy is often used to treat stage 1 and 2 lymphomas, when the cancer cells are in only one part of the body. Treatment is normally given daily, Monday to Friday, over the space of three to four weeks. You should not have to stay in hospital between appointments.
Radiotherapy itself is painless, but it has some common side effects. These can vary, depending on which part of your body is being treated. For example, if the affected lymph nodes are in your throat, radiotherapy can lead to a sore throat, while treatment to the head can lead to hair loss.
Other common side effects include:
- dry mouth
- loss of appetite
People who are diagnosed with the rare lymphocyte predominant type of Hodgkin's lymphoma may have a type of biological therapy called rituximab.
Rituximab attaches itself to the surface of a cancerous cell and stimulates the immune system to attack and kill the cell.
It is administered directly into your vein over the course of a few hours. The usual recommended dose is to have it once a week for four weeks.
It is common to experience flu-like symptoms when you are being treated with rituximab. Possible symptoms include:
- fever or chills
- muscle pain
You may be given additional medication to prevent or lessen side effects. Side effects should improve over time as your body gets used to rituximab.
Steroids are used in combination with chemotherapy to treat some cases of Hodgkin's lymphoma. Research has shown that using steroids makes the chemotherapy more effective.
Steroids are given intravenously, usually at the same time as your chemotherapy. A short-term course of steroids, lasting no more than a few months, is usually recommended as this limits the number of side effects you could have. Common side effects of short-term steroid use include:
- increased appetite, which can lead to weight gain
- an increase in your energy levels
- problems sleeping
On rare occasions, you may have to take steroids on a long-term basis. Side effects of long-term steroid use include:
- swelling in your hands, feet and eyelids
- weight gain
- raised blood pressure
- a slightly higher risk of developing infections
Cancer Research UK provides more information about the treatment of Hodgkin's lymphoma and living with Hodgkin's lymphoma.
An intensive, high-dose programme of chemotherapy can irreversibly damage the stem cells in your bone marrow.
Stem cells are important as they have the ability to create other specialised cells, such as red and white blood cells.
If the possibility of bone marrow damage is high, your treatment team will take a small sample of healthy stem cells from your blood. These stem cells can be kept until your treatment is complete, and then they will be used to stimulate the production of new bone marrow. This procedure is known as an autologous stem cell transplant. Read more about stem cell transplants.
Being immunocompromised (having a weakened immune system) is a common complication of lymphoma. Even if your lymphatic system is restored to normal, many of the medications that treat lymphoma weaken your immune system.
This means you are more vulnerable to infections, and there is an increased risk of developing serious complications from infections. You may be advised to take regular doses of antibiotics to prevent infections occurring.
Report any symptoms of an infection to your doctor or care team immediately because prompt treatment may be needed to prevent serious complications.
Symptoms of infection include:
- aching muscles
Also make sure that all of your vaccinations are up to date. Your doctor or care team will advise you on this.
Many of the treatments for lymphoma can cause infertility. Infertility is often temporary, but in some cases it may be a permanent side effect.
Your treatment team will estimate the risk of infertility in your specific circumstances.