Tests for lymphoma

Lymph node biopsy

If you have swollen lymph nodes, your doctor will organise a biopsy. This is when some cells and tissues are removed from the enlarged lymph node. A biopsy can be done in one of two ways – an excision biopsy or a core biopsy.

Excision biopsy

• The whole lymph node or part of it is removed with surgery. This may be done as day surgery, or you may stay in hospital for a few days.
• Depending on where the lymph node is, you’ll have either a local or general anaesthetic.
• The wound is usually closed with stitches. These will be removed about a week later.
• An excision biopsy helps ensure an accurate diagnosis. It is the preferred way to take a biopsy for lymphoma because it reduces the risk that the sample will be too small to examine.

Core biopsy

• A hollow needle is inserted into the lymph node to remove some cells and a small piece of tissue. It is usually done as day surgery with a local anaesthetic.
• Ultrasound or CT scan may be used to guide the needle to the correct lymph node.
• A core biopsy is usually done when it is difficult to remove the lymph node or when lymphoma has returned after treatment.
• Depending on the pathology results, you may need to have a follow-up excision biopsy.

After the biopsy

The biopsy sample is sent to a laboratory for examination under a microscope by a specialist doctor called a pathologist. The results will usually be ready in 7–10 days. This waiting period can be an anxious time, and it may help to talk to a supportive friend, relative or health professional about how you are feeling.

If the pathologist finds lymphoma cells, they can work out the type with further tests on the biopsy sample.

These tests may include:

Immunophenotyping – This test looks for differences between types of cells. It does this by identifying markers called antigens, which are found on the surface of cells. If lymphoma is found, immunophenotyping can work out the subtype by looking at the antigen pattern.

FISH tests – This stands for fluorescence in situ hybridisation. This test looks at changes inside lymphoma cells. It helps doctors confirm the type of lymphoma and choose the most suitable treatment.

Genomic and cytogenetic tests – These tests are more often used in diagnosing non-Hodgkin lymphoma. Genomic tests look for gene changes, faults or molecular targets. These gene changes are not the same as gene changes passed through families. Cytogenetic tests look for abnormalities in chromosomes.

Having tests to look for changes in the genes and chromosomes is becoming more common. The results of these tests help doctors recommend the most suitable treatment options. The results also help work out the chance of lymphoma coming back (relapsing) after a period of improvement (remission).

Further tests

If the biopsy of the enlarged lymph node shows that you have lymphoma, you may have further tests to find out the extent and type of lymphoma in your body. This is called staging.

This section describes tests that are commonly used to help stage lymphoma. You may not need to have all these tests – most people will have blood tests and at least one imaging test. Some tests may be repeated to check how well the treatment is working.

Blood tests

Your doctor will take a blood sample to see how well your kidneys and liver are working, and to check the number of blood cells (a full blood count). Low blood counts before treatment may suggest that the cancer has spread to the bone marrow. You will also have regular blood tests to check the effects of treatment on your total number of red blood cells, white blood cells and platelets.

Imaging tests

CT scan

A CT (computerised tomography) scan uses x-ray beams to create a detailed three-dimensional picture of an area inside the body. Your chest, abdomen and pelvis will be scanned to check the extent of the lymphoma.

Before the scan, you may be asked to drink a liquid or have a special dye called contrast injected into a vein. This helps ensure that anything unusual can be seen more clearly. The dye may cause you to feel hot all over and give you a strange taste in your mouth, and you could feel as if you need to pass urine (pee). These reactions usually go away after a few minutes but tell the clinical team if you feel unwell.

The CT scanner is large and round like a doughnut. You will lie on a table that moves in and out of the scanner. The scan is painless. While it can take 30–45 minutes to prepare for the scan, the scan itself takes only a few minutes. Most people can go home as soon as the scan is over.

PET–CT scan

This specialised test combines a positron emission tomography (PET) scan with a non-contrast CT scan to produce a three-dimensional colour image.

For the PET scan, you will be injected in the arm with a glucose (sugar) solution containing a small amount of radioactive material. You will be asked to sit quietly for 30–90 minutes while the solution moves around your body. The scan itself takes about 30 minutes. Cancer cells take up more of the solution than normal cells and appear brighter on the scan.

Clinic staff will tell you how to prepare for the scan, particularly if you have diabetes. You will be encouraged to drink plenty of water to help the glucose solution leave your body.

The CT scan is used to help work out the precise location of any areas of concern shown on the PET scan.

Chest x-ray

Some people may have an x-ray of the chest area to see if the lymphoma has spread to the lymph nodes in their chest or lungs. This is usually for people with symptoms such as shortness of breath or chest pain. An x-ray is painless and takes only a few minutes.

Ultrasound

An ultrasound uses soundwaves to create a picture of the internal organs. This test is most commonly used to guide the needle to the correct lymph node during a core biopsy. An ultrasound is painless and takes only a few minutes.

MRI scan

MRI (magnetic resonance imaging) scans are not commonly used for people with lymphoma but may be used to check the brain and spinal cord. The MRI scan uses a combination of a powerful magnet and radio waves to create detailed pictures of areas inside the body.

You will lie on a treatment table that slides into a metal cylinder. The test is painless, but some people find lying in the cylinder noisy and confined. An MRI scan takes 30–60 minutes. People with some types of pacemakers or other metallic objects cannot have an MRI.

Bone marrow biopsy

You may need to have a biopsy to check whether lymphoma cells have spread to the bone marrow. A bone marrow biopsy is more commonly used in non-Hodgkin lymphoma, particularly to help in staging.

A bone marrow biopsy is done in 2 steps:

Bone marrow aspiration – The doctor inserts a needle into the bone at the back of your pelvis to remove a small sample of fluid (aspirate) from the bone marrow. A local anaesthetic is given before.

Bone marrow trephine – A second needle is used to take a matchstick-wide sample of both bone and bone marrow tissue. You will lie still while a local anaesthetic is injected into your pelvis (hip) to numb the area. To help you feel relaxed, you may be offered light sedation or medicine that you breathe in through an inhaler.

A bone marrow biopsy takes about 30 minutes. It is usually done as an outpatient procedure, and you don’t need to stay in hospital overnight.

You may feel some pressure or discomfort during the biopsy. If you feel uncomfortable afterwards, ask a member of your health care team about pain medicine. You will need to lie flat in bed for another 30 minutes after the biopsy to make sure there is no bleeding.

The bone marrow sample is examined under a microscope to check for lymphoma cells. Results are usually available in 2–7 days.