Non-Hodgkin lymphoma

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 non-Hodgkin lymphoma, the affected 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 the body more vulnerable to infection.

About 80% of all lymphomas diagnosed are non-Hodgkin lymphoma*. In the UK, more than 12,000 cases are diagnosed each year*. Non-Hodgkin lymphoma can occur at any age, but your chances of developing the condition increase as with age, with most cases diagnosed in people over 65*. Slightly more men than women are affected.

The exact cause of non-Hodgkin lymphoma is unknown, but there are several risk factors associated with the disease. These include:

• 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 following an organ transplant
• Having an autoimmune condition (a condition caused by problems with the immune system), such as lupus or Sjogren’s syndrome
• Being previously exposed to the Epstein-Barr virus (a common virus that causes glandular fever)
• Being previously exposed to the Human T-cell lymphotropic virus (HTLV)
• Having a Helicobacter pylori infection (a common bacterial infection that usually infects the lining of the stomach and small intestine)
• Having received chemotherapy or radiotherapy for an earlier cancer
• Having coeliac disease (an adverse reaction to gluten that causes inflammation of the small bowel)

Symptoms of non-Hodgkin lymphoma

The most common symptom of non-Hodgkin 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 a lymph node, which is a pea-sized lump of tissue found throughout the body containing white blood cells that help to fight against infection. Some people with non-Hodgkin lymphoma also have other more general symptoms. These can include:

• Night sweats
• Unexplained weight loss
• A high temperature (fever)
• A persistent tiredness or fatigue
• Difficulty recovering from infections or developing infections more often
• 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 stomach is affected, you may have abdominal pain or indigestion.

If any of these symptoms apply to you, or if you have any concerns about similar symptoms, it is essential that you see your doctor at once, as your chances of recovery are much higher if your cancer is diagnosed early.

Diagnosis of non-Hodgkin lymphoma

Your consultant or oncologist will perform a test called a biopsy, which is the only way to confirm a diagnosis of Hodgkin lymphoma. This is a minor surgical procedure where a sample of affected lymph node tissue is removed.

If the patient tests positive for non-Hodgkin lymphoma, a range of further tests will be carried out to determine the type and spread of the cancer. These include:

• A blood test to measure the levels of different types of blood cells
• A lumbar puncture, where a needle is used to extract a sample of cerebrospinal fluid (fluid that surrounds and protects your spine) from your back. The fluid is tested to determine whether leukaemia has reached your nervous system, and this test is carried out using local anaesthetic
• A bone marrow biopsy, during which a haematologist will take a small sample of bone marrow to examine under a microscope. This involves inserting a needle into a large bone, usually the hip bone, to extract the marrow, and is done under local anaesthetic
• An MRI scan, which is a procedure that uses a magnet, radio waves, and a computer to make a series of detailed pictures of areas inside the body
• A PET scan, which uses a very small amount of an injected radioactive drug to show where cells are active in the body
• A CT scan, which shows a 3D image of the area being looked at

Types of non-Hodgkin lymphoma

Many of the diagnostic tests used to confirm non-Hodgkin lymphoma can also be used to identify the type of the disease. Knowing this helps the doctors to tailor the treatment plan to the individual needs of the patient. There are more than 30 types of non-Hodgkin lymphoma, including diffuse large B-cell lymphoma, follicular lymphoma and mantle cell lymphoma.

Treatment of non-Hodgkin lymphoma

Patients with non-Hodgkin lymphoma are treated by a specialist multidisciplinary team. This team works together to create a treatment plan to suit the individual needs of the patient.

Initially, most patients with non-Hodgkin lymphoma are treated with the ‘Wait-and-See’ approach, which is used when the disease is low-grade and the patient doesn’t show any troubling symptoms. At this point, there is no advantage to starting treatment and a period of ‘watchful waiting’ is often recommended as some people take many years to develop troublesome symptoms in these circumstances.

Once symptoms are present, there are a variety of treatment options available, including:

• Chemotherapy, which involves the use of chemical agents which are toxic to cancer cells, destroying them and preventing them from spreading to different areas. This can be given by injection or in tablet form. For non-Hodgkin lymphoma patients, there is the option of high or low dose chemotherapy, depending on progression and general health
• Radiotherapy, which is where high-energy rays are used to destroy the cancer cells
• Monoclonal Antibody Therapy, which is a medication that attaches itself to the surface of cancerous cells and stimulate the immune system to attach and kill these cells. This treatment is often given in combination with chemotherapy
• Steroid medication, which is often used to make chemotherapy more effective

In a few cases where the initial cancer was very small and was removed during a biopsy, no further treatment may be needed.