ON THIS PAGE: You will find a list of common tests, procedures, and scans that doctors use to find the cause of a medical problem. To see other pages, use the menu.
Doctors use many tests to find, or diagnose, cancer. They also do tests to learn if cancer has spread to another part of the body from where it started. If this happens, it is called metastasis. For example, imaging tests can show if the cancer has spread. Imaging tests show pictures of the inside of the body. Doctors may also do tests to learn which treatments could work best.
For most types of cancer, a biopsy is the only sure way for the doctor to know whether an area of the body has cancer. In a biopsy, the doctor takes a small sample of tissue for testing in a laboratory. If a biopsy is not possible, the doctor may suggest other tests that will help make a diagnosis.
This list describes options for diagnosing this type of cancer. Not all tests listed below will be used for every child. Your child’s doctor may consider these factors when choosing a diagnostic test:
The type of cancer suspected
Your signs and symptoms
Your age and medical condition
The results of earlier medical tests
In addition to a physical examination, the following tests may be used to diagnose osteosarcoma. A health care team with experience diagnosing and treating bone tumors should perform these tests.
- X-ray. An x-ray is a way to create a picture of the structures inside of the body, using a small amount of radiation. The doctor will take an x-ray of the area where there is a lump or swelling. Osteosarcoma usually shows certain common features on an x-ray.
- Computed tomography (CT or CAT) scan. A CT scan creates a 3-dimensional picture of the inside of the body using x-rays taken from different angles. A computer then combines these images into a detailed, cross-sectional view that shows any abnormalities or tumors. A CT scan can also be used to measure the tumor’s size. Sometimes, a special dye called a contrast medium is given before the scan to provide better detail on the image. This dye can be injected into a patient’s vein or given as a pill to swallow.
- Magnetic resonance imaging (MRI). An MRI uses magnetic fields, not x-rays, to produce detailed images of the body. MRI can also be used to measure the tumor’s size. A special dye called a contrast medium is given before the scan to create a clearer picture. This dye can be injected into a patient’s vein or given as a pill to swallow.
An MRI creates more detailed pictures than CT scans. Sometimes, it helps find a smaller tumor. Also, an MRI provides more exact pictures of the tumor and the surrounding healthy tissue. This can help the orthopedic surgeon plan surgery. An orthopedic surgeon is a doctor who specializes in surgery on the bones. Surgery removes the tumor-containing area of bone along with a portion of the surrounding healthy tissue called the margin.
- Positron emission tomography (PET) or PET-CT scan. A PET scan is usually combined with a CT scan (see above), called a PET-CT scan. However, you may hear your doctor refer to this procedure just as a PET scan. A PET scan is a way to create pictures of organs and tissues inside the body. A small amount of a radioactive sugar substance is injected into the patient’s body. This sugar substance is taken up by cells that use the most energy. Because cancer tends to use energy actively, it absorbs more of the radioactive substance. A scanner then detects this substance to produce images of the inside of the body.
- Bone scan. A bone scan uses a radioactive tracer to look at the inside of the bones. The tracer is injected into a patient’s vein. It collects in areas of the bone, and a special camera detects it. Healthy bone appears gray to the camera. Meanwhile, areas of injury, such as those caused by a tumor, appear dark. However, areas where new bone is being formed also appear dark. This is normal.
- Arteriogram (or angiogram). An arteriogram is a way for doctors to see inside the arteries. A small amount of a contrast medium is injected into an artery, making it appear on an x-ray. A surgeon may use this test to help plan surgery.
A biopsy is the removal of a small amount of tissue for examination under a microscope. Other tests can suggest that a tumor is present, but only a biopsy can make a definitive diagnosis. A pathologist then analyzes the sample(s). A pathologist is a doctor who specializes in interpreting laboratory tests and evaluating cells, tissues, and organs to diagnose disease.
A doctor who specializes in bone tumors should perform the biopsy. The biopsy typically involves surgery. However, sometimes, the doctor performs a needle biopsy. A needle biopsy uses a hollow needle inserted into the tumor. The doctor may analyze the genes or other features of the cancer cells to tell osteosarcoma apart from other types of cancer.
After diagnostic tests are done, your child’s doctor will review all of the results with you. If the diagnosis is cancer, these results also help the doctor describe the location(s) of the cancer. This is called staging.
The next section in this guide is Stages. It explains the system doctors use to describe the extent of the disease. Or, use the menu to choose another section to continue reading this guide.