Once Ewing sarcoma has been diagnosed, you’ll likely need other tests to learn more about the cancer. These tests can help show if the cancer has grown into nearby areas or spread to other parts of the body. The test results help your healthcare providers decide the best ways to treat the cancer. If you have any questions about these or other tests, be sure to talk with your healthcare team.
Imaging tests to look for cancer spread
A CT scan is also called a CAT scan or spiral CT scan. It uses X-rays to make detailed pictures of the inside of your body. After diagnosing Ewing sarcoma, a CT scan may be done on your chest or abdomen (belly). A CT scan of your chest is commonly done to see if the cancer has spread to your lungs.
To have the test, you lie still on a table as it slowly slides through the center of the ring-shaped CT scanner. Many X-rays are taken as the table slides through. A computer uses the data from the X-rays to make detailed pictures. A CT scan doesn't hurt. You may be asked to briefly hold your breath a few times during the scans. In some cases, you’ll get a contrast medium put into a vein and into your blood before the scan. This helps tumor details show up better during the scan.
An MRI uses magnets, radio waves, and a computer to make detailed pictures of the inside of your body. An MRI may be used to help diagnose Ewing sarcoma, and may also be used to learn the exact size and extent of the spread of the main tumor. MRI can be used to look for areas of cancer spread in other parts of your body, too. In some cases, you’ll get a contrast dye injected into your blood before getting the scan.
MRIs don’t hurt. But they can take a long time to do (up to an hour or so). During that time, you’ll need to lie still on a table that’s moved into a long, narrow tube. If you have a fear of enclosed spaces or are a young child, your healthcare provider may give a sedative to help you stay calm during the test. Newer, more open MRI machines can sometimes be used instead. But the images may not be as clear. The scanner makes loud banging and whirring noises during the test. You can ask for earplugs if you think the noise will bother you.
A bone scan looks at your whole skeleton, so your provider can look for the spread of bone tumors anywhere in your body. For this test, a slightly radioactive substance that's attracted to changes in bones (which might be from cancer) is injected into your vein. The substance travels through the bloodstream and collects in areas of abnormal bone growth. A special camera can then show where this substance collects. More detailed tests are then needed to get a close look at these areas.
Many times, a PET scan is used instead of a bone scan.
A PET scan can look for cancer that has spread to the bones, as well as other parts of the body. The picture isn’t as detailed as a CT scan. But a PET scan can show even small abnormal or changed areas throughout your body.
For this test, a mildly radioactive sugar is injected into a vein. Cancer cells absorb more of this sugar than normal cells, and the radioactive material shows up as "hot" spots on the images taken during the scan. To have the scan, you’ll need to lie still on a table that’s pushed into the PET scanner. The whole process may take several hours.
Some machines can do a PET scan and CT scan at the same time (PET/CT scan). This can give your healthcare provider the details of a CT scan along with the findings of the PET scan to learn more about the cancer and the cancer spread.
Procedures to learn more about the cancer
Bone marrow aspiration and biopsy
These tests are done at the same time and may be needed after Ewing sarcoma has been diagnosed. They can help show if the cancer has spread to the bone marrow. This is the soft, spongy, inner part of many bones. For these tests, your healthcare provider uses hollow needles to take out tiny samples of bone marrow and bone. The bone marrow and bone is usually taken from the back of your hip bones.
Teens and adults may be awake when this is done (with the area numbed), but children are usually given medicines to make them sleep during the test.
The bone and bone marrow samples are sent to a lab where tests are done to check for cancer cells.
Blood tests are commonly done after Ewing sarcoma has been diagnosed. They can be used to get an idea of your overall health. They can show how well your bone marrow, kidneys, liver, and other organs are working.