Hodgkin lymphoma is an uncommon cancer that develops 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 Hodgkin lymphoma, B-lymphocytes (a particular type of lymphocyte) 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 lymphoma is a painless swelling in a lymph node, usually in the neck, armpit or groin.
Who is affected?
Hodgkin lymphoma can develop at any age, but it mostly affects young adults in their 20s and older adults over the age of 70. Slightly more men than women are affected.
Around 1,900 people are diagnosed with Hodgkin lymphoma in the UK each year.
What causes Hodgkin lymphoma?
The exact cause of Hodgkin lymphoma is unknown. However, your risk of developing the condition is increased if you have a medical condition that weakens your immune system, you take immunosuppressant medication, or you have previously been exposed to a common virus called the Epstein-Barr virus, which causes glandular fever.
You also have an increased risk of developing Hodgkin lymphoma if a first-degree relative (parent, sibling or child) has had the condition.
How Hodgkin lymphoma is diagnosed
The only way to confirm a diagnosis of Hodgkin lymphoma is by carrying out a biopsy.
This is a minor surgical procedure where a sample of affected lymph node tissue is removed and studied in a laboratory.
Treatment and outlook
Hodgkin 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.
Your recommended treatment plan will depend on your general health and age, because many of the treatments can put a tremendous strain on the body. How far the cancer has spread is also an important factor in determining the best treatment.
The main treatments used are chemotherapy, followed by radiotherapyor chemotherapy alone. Surgery is not generally used as a treatment for the condition.
Overall, more than 80% of people with Hodgkin lymphoma will live at least five years and most of these will be cured. However, there is a risk of long-term problems after treatment, including infertility and an increased risk of developing another type of cancer in the future.
Symptoms of Hodgkin lymphoma
The most common symptom of Hodgkin lymphoma is a swelling in the neck, armpit or groin. The swelling is usually painless, although some people find that it aches.
The swelling is caused by an excess of affected lymphocytes (white blood cells) collecting in a lymph node (also called lymph glands). Lymph nodes are pea-sized lumps of tissue found throughout the body. They contain white blood cells that help to fight infection.
However, it is highly unlikely that you have Hodgkin lymphoma if you have swollen lymph nodes, as these glands often swell as a response to infection..
Some people with Hodgkin lymphoma also have other more general symptoms. These can include:
unexplained weight loss
a high temperature (fever)
persistent tiredness or fatigue
difficulty recovering from infections or developing infections more often
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 abdomen (tummy) is affected, you may have abdominal pain or indigestion.
A few people with Hodgkin 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. It can also cause excessive bleeding, such as nosebleeds, heavy periodsand spots of blood under the skin.
In some cases, people with Hodgkin lymphoma experience pain in their lymph glands when they drink alcohol.
When to seek medical advice
See your GP if you have any of the above symptoms, particularly if you have persistently swollen glands with no other signs of infection.
While the symptoms are unlikely to be caused by Hodgkin lymphoma, it is best to get them checked out.
Causes of Hodgkin lymphoma
Hodgkin lymphoma is caused by a change (mutation) in the DNA of a type of white blood cell called B lymphocytes, although the exact reason why this happens is not known.
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 lymphocytes 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 lymphocytes to spread into other parts of your body, such as your bone marrow, spleen, liver, skin and lungs.
Who is most at risk?
While the cause of the initial mutation that triggers Hodgkin lymphoma is unknown, a number of factors can increase your risk of developing the condition:
having a medical condition that weakens your immune system, such as HIV
having medical treatment that weakens your immune system –for example, taking medication to suppress your immune system after an organ transplant
being previously exposed to the Epstein-Barr virus (EBV), a common virus that causes glandular fever
having previously had non-Hodgkin lymphoma, possibly because of treatment with chemotherapy or radiotherapy
Hodgkin lymphoma isn't infectious and isn't thought to run in families. Although your risk is increased if a first-degree relative (parent, sibling or child) has had lymphoma, it is not clear if this is because of an inherited genetic fault or lifestyle factors.
Hodgkin lymphoma can occur at any age, although most cases are diagnosed in people in their 20s or 70s. The condition is slightly more common in men than women.
Diagnosing Hodgkin lymphoma
If you go to see your GP concerned about symptoms of Hodgkin lymphoma, they will ask about your health and carry out a simple physical examination.
If necessary, your GP will refer you to hospital for further tests. In hospital it is likely that a biopsy will be carried out, as this is the only way to confirm a diagnosis of Hodgkin lymphoma.
A biopsy involves removing some or all of an affected lymph node, which is then studied in a laboratory.
Biopsies are small operations that can often 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 (where you are asleep).
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 Hodgkin lymphoma you have, which is an important factor in planning your treatment.
If a biopsy confirms a diagnosis of Hodgkin lymphoma, further testing will be required to check how far the lymphoma has spread. This allows a doctor to diagnose the stage of your lymphoma.
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 kidneys are working
bone marrow sample – another biopsy may be carried out to see if the cancer 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 the cancer has spread to your chest or lungs
computerised tomography (CT) scan – this scan takes a series of X-rays that build up a 3D picture of the inside of the body to check the spread of the cancer
magnetic resonance imaging (MRI) scan – this scan uses strong magnetic fields to build up a detailed picture of areas of your body to check the spread of the cancer
positron emission tomography (PET) scan – this is a type of scan that measures the activity of cells in different parts of the body and can check the spread of the cancer and the impact of treatment; it is usually taken at the same time as a CT scan to show precisely how the tissues of different sites of the body are working
Stages of Hodgkin lymphoma
When the testing is complete, it should be possible to determine the stage of your lymphoma. Staging means scoring the cancer by how far it has spread.
The main stages of Hodgkin lymphoma are:
stage 1 – the cancer is limited to one group of lymph nodes, such as your neck or groin nodes either above or below your diaphragm (the sheet of muscle underneath the lungs)
stage 2 – two or more lymph node groups are affected, either above or below the diaphragm
stage 3 – the cancer has spread to lymph node groups above and below the diaphragm
stage 4 – the cancer has spread through the lymphatic system and is now present in organs or bone marrow
Health professionals also add the letters "A" or "B" to your stage to indicate whether or not you have certain symptoms.
"A" is put after your stage if you have no additional symptoms other than swollen lymph nodes. "B" is put after your stage if you have additional symptoms of weight loss, fever or night sweats.
Treating Hodgkin lymphoma
Hodgkin lymphoma can usually be treated successfully with chemotherapy alone, or chemotherapy followed by radiotherapy.
Your treatment plan
Your specific treatment plan will depend on your general health and your age, as many of the treatments can put a tremendous strain on the body. How far the cancer has spread is also an important factor in determining the best treatment.
Discussions about your treatment plan will usually take place with several doctors and other health professionals who specialise in different aspects of treating lymphoma. This is known as a multidisciplinary team (MDT).
Your MDT will recommend the best treatment options for 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.
The main treatments for Hodgkin lymphoma are chemotherapy alone, or chemotherapy followed by radiotherapy. In a few cases, chemotherapy may be combined with steroid medication or a medication called rituximab.
Surgery is not generally used to treat the condition, except for the biopsy used to diagnose it.
Overall, treatment for Hodgkin lymphoma is highly effective and most people with the condition are eventually cured.
The main treatments you may have are described in more detail below.
Chemotherapy is a type of treatment for cancer where medicine is used to kill cancer cells. This medication can be given in a number of different ways depending on the stage of your cancer.
If doctors think that your cancer is curable, you will normally receive chemotherapy through a drip directly into a vein (intravenous chemotherapy). If a cure is unlikely, you may only need to take chemotherapy tablets to help relieve your 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. However, 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 can have several side effects, the most significant of which is potential damage to your bone marrow. This can interfere with the production of healthy blood cells and cause the following problems:
increased vulnerability to infection
bleeding and bruising more easily
If you experience these problems, treatment may need to be delayed so you can produce more healthy blood cells. Growth factor medicines can also stimulate the production of blood cells.
Other possible side effects of chemotherapy include:
nausea and vomiting
loss of appetite
infertility, which may be temporary or permanent (see complications of Hodgkin lymphoma for more information)
Most side effects should pass once your treatment has finished. Tell your care team if the side effects become particularly troublesome, as there are treatments that can help.
If regular chemotherapy is unsuccessful or Hodgkin lymphoma returns after treatment, you may have a course of chemotherapy at a higher dose.
However, this intensive chemotherapy will destroy your bone marrow, leading to the problems mentioned above. You will therefore require a stem cell or bone marrow transplant to replace the damaged bone marrow.
Radiotherapy is most often used to treat early-stage Hodgkin lymphoma, where the cancer is only in one part of the body.
Treatment is normally given in short daily sessions, Monday to Friday, over the space of several weeks. You should not have to stay in hospital between appointments.
Radiotherapy itself is painless, but it can have some significant side effects. These can vary and will be directly related to the part of your body that is being treated. For example, treatment to your throat can lead to a sore throat, while treatment to the head can lead to hair loss.
Other common side effects include:
nausea and vomiting
loss of appetite
Most side effects are temporary, but there is a risk of long-term problems, including infertility and permanently darkened skin in the treatment area.
Steroid medication is sometimes used in combination with chemotherapy as a more intensive treatment for advanced cases of Hodgkin lymphoma, or where initial treatment has been ineffective.
The steroid medication is given intravenously, usually at the same time as your chemotherapy.
Common side effects of steroid medication include:
increased appetite, which can lead to weight gain
The side effects of steroid medication will usually start to improve once treatment finishes.
If you are diagnosed with a rare type of Hodgkin lymphoma called lymphocyte-predominant Hodgkin lymphoma, you may have chemotherapy in combination with a medication called rituximab.
Rituximab is a type of biological therapy called a monoclonal antibody. It attaches itself to the surface of cancerous cells and stimulates the immune system to attack and kill the cell.
It is given through a drip directly into a vein over the course of a few hours.
Side effects of the drug can include:
flu-like symptoms, such as headaches, fever and muscle pain
You may be given additional medication to prevent or reduce side effects. Any side effects should improve over time as your body gets used to the medication.
After your course of treatment ends, you will need to have regular follow-up appointments to monitor your recovery and check for any signs of the cancer returning.
These appointments will start off being every few weeks or months, but will become gradually less frequent over time.
Complications of Hodgkin lymphoma
Some people treated for Hodgkin lymphoma experience long-term problems, even if they have been cured.
Some of the main complications of Hodgkin lymphoma are described below.
Weakened immune system
Having a weakened immune system is a common complication of Hodgkin lymphoma and it can become more severe while you are being treated.
If you have a weak immune system, you are more vulnerable to infections and there is an increased risk of developing serious complications from infections. In some cases, you may be advised to take regular doses of antibiotics to prevent infections occurring.
It is also important to report any symptoms of an infection to your GP or care team immediately as prompt treatment may be needed to prevent serious complications.
Symptoms of infection include:
a high temperature (fever)
You should also make sure all of your vaccinations are up-to-date. However, it's important to speak to your GP or care team about this as it may not be safe for you to have "live" vaccines (vaccines containing a weakened form of the virus or organism being vaccinated against) until several months after your treatment finishes.
Examples of live vaccines include the shingles vaccine, the BCG vaccine (against tuberculosis) and the MMR vaccine (against measles, mumps and rubella).
Chemotherapy and radiotherapy for Hodgkin lymphoma can causeinfertility. This is sometimes temporary, but it can be permanent.
Your care team will estimate the risk of infertility in your specific circumstances and let you know what your options are.
In some cases, it may be possible for men to store samples of their sperm and for women to store their eggs before treatment so these can be used to try for a baby afterwards.
People who have had Hodgkin lymphoma are more likely to get lymphoma, leukaemia or other cancers in the future. Chemotherapy and radiotherapy further increase this risk.
"Second cancers", such as breast cancer or lung cancer, usually develop more than 10 years after you were treated for Hodgkin lymphoma. In rare cases, other types of cancer, such as leukaemia or other lymphomas, develop after only a few years.
You can help reduce your risk of a second cancer by adopting a healthy lifestyle through not smoking, maintaining a healthy weight with a balanced diet, and getting regular exercise.
You should report any symptoms that might suggest another cancer to your GP at an early stage and attend any cancer screening appointments you're invited to.
Other health problems
The risk of developing other health conditions in the future, such as cardiovascular disease and lung disease, is also higher in people who have had Hodgkin lymphoma.
You should report unexpected symptoms such as increasing shortness of breath to your GP for further advice.