Tests That Help Evaluate Hodgkin Disease
Once the diagnosis is established as Hodgkin disease, the second important part of diagnosis is assessing how advanced the disease is. Depending on where the initial lymph nodes are, you may need some or all of these tests:
Chest X-ray. Enlargement of lymph nodes in the chest caused by Hodgkin disease can usually be seen on a plain chest X-ray.
Computed tomography (CT) scan of your chest, abdomen, and pelvis. In this test, an X-ray beam takes pictures of the body from many angles. A computer puts these pictures together, making a detailed cross-section of the body. The doctor may enhance the pictures by asking you to drink or by injecting a contrast material or dye into your vein before the X-rays. An IV line may be placed before the CT scan so contrast material can be given to you through the IV site. You may experience a warm sensation, usually in the face, if contrast material is given to you through an IV. Be sure to tell your doctor or health care provider if you are allergic or have had a reaction to the contrast material in the past. A CT scan can show groups of lymph nodes, an enlarged spleen, or abnormalities in your liver.
Magnetic resonance imaging (MRI). An MRI uses magnets and radio waves to take pictures of the inside of the body. MRIs are not as useful as CT scans, but may tell whether there is bone marrow involvement with Hodgkin disease. They can also be useful if your doctor thinks the cancer might have spread to the brain and spinal cord.
PET scan. This test is useful because it can give quick information on the presence of lymphoma almost anywhere in the body. For this test, you are injected with a radioactive sugar. The cells of Hodgkin disease take up this sugar, which shows up on a scan. The picture from a PET scan is not finely detailed like a CT scan, but it provides important information about the location of the lymphoma throughout the body. It is especially helpful in telling whether the lymphoma is responding to treatment. Newer machines combine PET and CT scans. This lets the doctor compare areas of higher radioactivity on the PET scan with the more detailed image of the CT scan.
Gallium scan. For this test, you first have a gallium isotope injected into a vein in your arm. One to 3 days later, you’ll go to the hospital or clinic to have a special camera take pictures of your body. Doctors use this scan to look in your chest and to see whether any active lymphoma has been left behind after treatment. This test is rarely used anymore, as it has largely been replaced by PET scanning.