ON THIS PAGE: You will find a list of the common tests, procedures, and scans that doctors can use to find out what’s wrong and identify the cause of the problem. To see other pages in this guide, use the colored boxes on the right side of your screen, or click “Next” at the bottom.
Doctors use many tests to diagnose a tumor and find out if it has metastasized (spread). Some tests may also determine which treatments may be the most effective. For most types of tumors, a biopsy is the only way to make a definitive diagnosis. If a biopsy is not possible, the doctor may suggest other tests that will help make a diagnosis. Imaging tests may be used to find out whether the tumor has spread. This list describes options for diagnosing astrocytoma, and not all tests listed will be used for every person. Your child’s doctor may consider these factors when choosing a diagnostic test:
- Age and medical condition
- Type of tumor suspected
- Signs and symptoms
- Previous test results
In addition to a physical examination, the following tests may be used to diagnose astrocytoma:
Computed tomography (CT or CAT) scan. A CT scan creates a three-dimensional picture of the inside of the body with an x-ray machine. 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 contrast medium (a special dye) is injected into a vein or given orally (by mouth) to provide better detail.
Magnetic resonance imaging (MRI). An MRI uses magnetic fields, not x-rays, to produce detailed images of the body. A contrast medium may be injected into a patient’s vein or given orally to create a clearer picture.
Biopsy. Other tests can suggest that a tumor is present, but only a biopsy can make a definite diagnosis. For astrocytoma, a biopsy is done to determine the type and grade of the tumor. A neurosurgeon (a doctor who specializes in treating a CNS tumor using surgery) will remove a small piece of tissue from the tumor. The sample removed during the biopsy is analyzed by a pathologist (a doctor who specializes in interpreting laboratory tests and evaluating cells, tissues, and organs to diagnose disease).
After these diagnostic tests are done, your child’s doctor will review all of the results with you. If the diagnosis is astrocytoma, these results also help the doctor describe the tumor; this is called staging and grading.
Choose “Next” (below, right) to continue reading this guide to learn about the different stages and grades for astrocytoma. Or, use the colored boxes located on the right side of your screen to visit any section.