Primary Bone Cancer: Tests to Check the Extent of the Cancer
If your doctor thinks you have primary bone cancer (cancer that started in your bones), he or she may order more tests. These tests can help your doctor learn more about the type of cancer and its specific location. When your doctor thinks the tumor is cancer, he or she will often order these tests before a biopsy. You will likely have more than 1 of these tests. These tests can help show if the cancer has grown into nearby areas or spread to other parts of your body. If you do have cancer, the test results help your healthcare providers decide the best options to treat it. If you have any questions about these or other tests, be sure to talk with your healthcare team.
The tests you may have can include:
An MRI uses magnets, radio waves, and a computer to create detailed pictures of the inside of your body. This test can be helpful for showing the shape of the bone tumor and if it has grown into nearby areas.
MRIs are not painful. But they can take a long time to complete, up to 1 hour. During that time you must lie still on a table that is moved into a long, narrow tube. The scanner is a small space. If you are uncomfortable in small spaces, you may be given a sedative to relax you. Take this before the test. Some hospitals and clinics have open MRI scanners. These are less confining, but the images may not be as sharp in some cases. When the scanner is working, it can be very loud. You may be given earplugs or headphones to wear. A 2-way intercom will let you talk to the technician during the test.
Because an MRI uses powerful magnets, you won’t be allowed to have anything metal in the room. Even eyeglasses and ballpoint pens can become dangerous objects when the magnets are turned on. If you have any kind of metal implant, such as a heart valve or a joint pin, you may not be able to have an MRI. This will depend on the type of metal your implant is made of. The equipment can also affect implants, such as a pacemaker.
A CT scan uses special X-rays to make detailed pictures of the inside of your body. During a CT scan, a doughnut-shaped X-ray machine scans the area of your body where your doctor suspects there is cancer.
A CT scan of the bone tumor can help show the extent of the tumor. CT scans can also help show if the cancer has spread to other parts of your body, such as your lungs.
A CT scan is painless. It is not invasive. You may first get an IV (intravenous) injection of contrast dye. The dye helps outline parts of your body so that they show up better on the CT scan.
During the test, you lie still on an exam table. The table slides through the center of the CT scanner. The scanner takes pictures of your body from many angles. The technician may ask you to hold your breath 1 or more times during the scan. A computer combines these pictures to create detailed cross-sectional images of your body.
Bone scans show areas of cell activity in bones, which can sometimes be a sign of cancer. Bone scans can often show where the cancer has spread. They can find metastases, or the spread of cancer, earlier than an X-ray. Bone scans don’t make detailed images. So other tests, such as X-rays of the bone, may be needed if any abnormal spots are seen.
For this test, a small amount of a mildly radioactive substance is injected into a vein. It travels through your blood vessels and collects in areas of abnormal bone growth. You need to wait about 2 hours between the injection and the bone scan. It’s recommended that you drink fluids during those 2 hours to help spread the dye around. You then lie on a table for about 30 minutes while a machine scans your body for the places the substance has collected. These are sometimes called hot spots. The amount of radioactive material used for this test is small. It shouldn’t be harmful to you or your family.
PET looks for cancer all over your body. A PET scan can sometimes tell if a tumor is cancer or not cancer (benign). For this test, a small amount of sugar (glucose) that has a mildly radioactive tracer will be put into your arm through an IV. Cancer cells absorb more of the radioactive sugar than normal cells, so they are more likely to show up on the test.
One hour after you get the radioactive tracer, you’ll get the PET scan. You will lie still on a table that is pushed into the PET scanner. It will rotate around you and take pictures. Other than the injection, a PET scan is painless. Some people are sensitive to the substance, and may have nausea, a headache, or vomiting. Some newer machines can do PET and CT scans at the same time, so areas that show up on the PET scan can be compared to the more detailed image of the CT scan.
Working with your healthcare provider
Your healthcare provider will talk with you about which tests you'll have. Make sure to get ready for the tests as instructed. Ask questions and talk about any concerns you have.
March 21, 2017
Bone tumors: Diagnosis and biopsy techniques. UpToDate.
Alteri, Rick, MD,Levin, Mark, MD