Tests for Hodgkin Lymphoma

Most people with Hodgkin lymphoma (HL) see their doctor because they have certain symptoms, or because they just don’t feel well and go in for a check-up.

If a person has signs or symptoms that suggest HL, exams and tests will be done to find out for sure and, if so, to determine the exact type.

Medical history and physical exam

The doctor will want to get a thorough medical history. You'll be asked about symptoms, possible risk factors, family history, and other medical conditions.

Next, the doctor will examine you (or your child), paying close attention to lymph nodes and other parts of the body that might be affected, including the spleen and liver. Because infections are the most common cause of enlarged lymph nodes, especially in children, the doctor will look for infection in the part of the body near any swollen lymph nodes.

The doctor also might order blood tests to look for signs of infection or other problems. If the doctor suspects that HL might be the problem, a biopsy of a swollen lymph node might be recommended.

Biopsies

Because swollen lymph nodes are more likely to be caused by something other than HL, like an infection, doctors often wait a few weeks to see if they shrink on their own as the infection goes away. You may be given antibiotics to see if they cause the nodes to shrink.

If the nodes don’t shrink or if they continue to grow, a lymph node (or a small piece of a node) is taken out to be checked in the lab. This procedure, called a biopsy, is the only way to be sure of the diagnosis. If it is HL, the biopsy can also show what type it is.

Types of biopsies

There are different types of biopsies. Doctors choose the best one to do based on the situation.

Excisional or incisional biopsy: This is the preferred and most common type of biopsy for an enlarged lymph node. The doctor cuts through the skin to remove the lymph node.

• If the whole lymph node is removed, it's an excisional biopsy.
• If a small part of a larger tumor or node is removed, it's an incisional biopsy.

If the node is just under the skin, the biopsy is fairly simple and can sometimes be done with numbing medicine (called local anesthesia). But if the node is inside the chest or abdomen (belly), you'll be sedated or given general anesthesia (where drugs are used to put you in a deep sleep). This type of biopsy almost always provides enough tissue to make a diagnosis of HL and tell the exact type.

Needle biopsy: A needle biopsy is less invasive than excisional or incisional biopsies because there's no cut in the skin. But the drawback is that it might not get enough tissue to diagnose HL (or find out which type it is). There are 2 main types of needle biopsies:

• A fine needle aspiration (FNA) biopsy uses a very thin, hollow needle attached to a syringe to take out (aspirate) a small amount of fluid and tiny bits of tissue.
• A core needle biopsy uses a larger needle to remove a slightly larger piece of tissue.

To biopsy an enlarged node just under the skin, the doctor can aim the needle while feeling the node. If a node or tumor is deep inside the body, a CT scan or ultrasound (see below) can be used to guide the needle.

Most doctors do not use needle biopsies (especially FNA biopsies) to diagnose HL. But if the doctor suspects that lymph node swelling is caused by an infection or by the spread of cancer from another organ (such as the breast, lungs, or thyroid), a needle biopsy might be the first type of biopsy done. An excisional biopsy may still be needed to diagnose HL, even after a needle biopsy has been done.

If HL has already been diagnosed, needle biopsies are sometimes used to check changes (like swollen nodes) in other parts of the body that might be from the lymphoma spreading or coming back after treatment.

Bone marrow aspiration and biopsy: These tests are not used to diagnose HL, but they may be done after the diagnosis is made to see if the lymphoma is in the bone marrow. The bone marrow aspiration and biopsy are usually done at the same time. The samples are taken from the back of the pelvic (hip) bone, but sometimes they may be taken from other bones.

In bone marrow aspiration, you lie on a table (either on your side or on your belly). After cleaning the skin over the hip, the doctor numbs the skin and the surface of the bone by injecting a local anesthetic (numbing drug). This may cause a brief stinging or burning feeling. A thin, hollow needle is then pushed into the bone, and a syringe is used to suck out a small amount of liquid bone marrow. Even with the anesthetic, most patients have some brief pain when the marrow is pulled out.

A bone marrow biopsy is usually done just after the aspiration. A small piece or core of bone and marrow is removed with a slightly larger needle that's pushed into the bone. The biopsy may also cause some brief pain.

Most children having a bone marrow aspiration and biopsy are either given medicine to make them drowsy or are given general anesthesia so they're asleep while it's done.

Lab tests of biopsy samples

All biopsy samples are looked at under a microscope by a pathologist (a doctor specially trained to recognize cancer cells), who will look for Hodgkin lymphoma cells (called Reed-Sternberg cells). Sometimes the first biopsy doesn't give a clear answer and more biopsies are needed.

Looking at the tissue samples under the microscope is often enough to diagnose HL (and what type it is), but sometimes more lab tests are needed.

Immunohistochemistry: This lab test looks for certain proteins on cells, such as CD15 and CD30. These are found on the surface of the Reed-Sternberg cells in classic Hodgkin lymphoma (cHL). Tests for other proteins may point to nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL), to non-Hodgkin lymphoma (rather than Hodgkin lymphoma), or maybe to other diseases.

Imaging tests

Imaging tests use x-rays, sound waves, magnetic fields, or radioactive particles to make pictures of the inside of the body. Imaging tests can be used in many ways, such as:

• To look for possible causes of certain symptoms, such as enlarged lymph nodes in the chest
• To help determine the stage (extent) of Hodgkin lymphoma
• To help show if treatment is working
• To look for possible signs of cancer coming back after treatment

These are the imaging tests most commonly used:

Chest x-ray

HL often enlarges lymph nodes in the chest. This can often be seen on a chest x-ray.

Computed tomography (CT) scan

A CT scan combines many x-rays to make detailed cross-sectional images of your body. This scan can help tell if any lymph nodes or organs in your body are enlarged. CT scans are useful for looking for HL in the neck, chest, abdomen (belly), and pelvis.

CT-guided needle biopsy: A CT scan can also be used to guide a biopsy needle into a suspicious area. For this procedure, a person lies on the CT scanning table while the doctor moves a biopsy needle through the skin and toward the area. CT scans are repeated until the needle is in the right place. A biopsy sample is then removed and sent to the lab to be looked at under a microscope.

Magnetic resonance imaging (MRI)

Like CT scans, MRIs show detailed images of soft tissues in the body. But MRIs use radio waves and strong magnets instead of x-rays. This test is rarely used in HL, but if the doctor is concerned about spread to the spinal cord or brain, MRI is very useful for looking at these areas. 

Positron emission tomography (PET) scan

For a PET scan, a slightly radioactive form of sugar is put into your blood. Over time, it collects in very active cells, like cancer cells. A special camera is then used to create a picture of the parts of the body where the radioactivity collected. The picture is not detailed like a CT or MRI scan, but it can give helpful information about your whole body.

PET scans can be used for many reasons in a person with HL:

• They can help show if an enlarged lymph node contains HL.
• They can help find small spots in the body that might be lymphoma, even if the area looks normal on a CT scan.
• They can help tell if the lymphoma is responding to treatment. Some doctors will repeat the PET scan after a few courses of chemotherapy. If it's working, the lymph nodes will no longer take up the radioactive sugar.
• They can be used after treatment to help decide if an enlarged lymph node still has cancer or if it's just scar tissue.

PET/CT scan: Some machines can do both a PET scan and a CT scan at the same time. This lets the doctor compare areas of higher radioactivity on the PET scan with the more detailed pictures from the CT scan. PET/CT scans often can help pinpoint the areas of lymphoma better than a CT scan alone.

Bone scan

A bone scan isn't usually done unless a person is having bone pain or has lab test results that suggest the lymphoma might have reached the bones.

For this test, a radioactive substance is injected into a vein. It travels to damaged areas of bone, and a special camera can then detect the radioactivity. HL sometimes causes bone damage, which may be picked up on a bone scan. But bone scans can’t show the difference between cancers and non-cancer problems, so more tests might be needed.

Other tests

Blood tests

Blood tests aren’t used to diagnose HL, but they can help your doctor get a sense of how advanced it is and how well you might tolerate certain treatments.

The complete blood count (CBC) is a test that measures the levels of different cells in the blood. People with HL can sometimes have abnormal blood counts. For example, if the lymphoma invades the bone marrow (where new blood cells are made) a person might have anemia (not enough red blood cells). A high white blood cell count is another possible sign of HL, although it can also be caused by infection.

A test called an erythrocyte sedimentation rate (ESR) can help measure how much inflammation is in the body. It can be elevated in some people with HL.

Blood tests might also be done to check liver and kidney function and to look for signs that the cancer might have reached the bones. Some women may have a pregnancy test.

Your doctor might also suggest other blood tests to look for signs of certain infections:

• HIV test: This may be done if you have abnormal symptoms that might be related to HIV infection.
• Hepatitis B and C virus test: Certain chemo drugs could cause problems if you have these infections. 

Tests of heart and lung function

These tests might be done if certain chemo drugs that could affect the heart or the lungs are going to be used.

• An echocardiogram (an ultrasound of the heart) or a MUGA scan can be used to check heart function.
• Lung (pulmonary) function tests (PFTs) can be used to see how well the lungs are working.