Craniopharyngioma - Childhood: Diagnosis

Approved by the Cancer.Net Editorial Board, 10/2022

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. Use the menu to see other pages.

Doctors use many tests to find, or diagnose, a tumor. Doctors may also do tests to learn which treatments could work best.

For most tumors, a biopsy is the only sure way for the doctor to know if an area of the body has a tumor. 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.

How craniopharyngioma is diagnosed

Your child’s doctor may consider these factors when choosing a diagnostic test:

  • The type of tumor suspected

  • Your child’s signs and symptoms

  • Your child’s age and general health

  • The results of earlier medical tests

There are different tests used for diagnosing craniopharyngioma. Not all tests described here will be used for every child.

  • Physical examination. The doctor will examine your child’s head and body and ask questions about the symptoms they are experiencing and their medical history. This may include tests to check your child’s vision, growth and development, and brain function.

  • Blood and/or urine tests. The doctor may recommend different blood tests, including tests that measure the levels of certain hormones. If your child has excessive thirst and increased urination, the doctor may recommend a water deprivation test to evaluate the production of a hormone that helps concentrate urine.

  • Biopsy. A biopsy is the only way to make a definite diagnosis, even if other tests can suggest that a tumor is present. During biopsy, part or all of the tumor is removed for examination under a microscope. For craniopharyngioma, a neurosurgeon may remove a piece of the tumor or the entire tumor during an operation. A neurosurgeon is a doctor who specializes in central nervous system (CNS) surgery. Then, a pathologist examines the tissue removed during the surgery under a microscope to make a diagnosis. A pathologist is a doctor who specializes in interpreting laboratory tests and evaluating cells, tissues, and organs to diagnose disease. A neuropathologist is a pathologist who specializes in CNS tissues and diseases. Usually, the neurosurgeon will try to safely remove as much of the tumor as possible while limiting damage to the brain (see Types of Treatment).

Imaging tests

Results of the physical examination and blood and/or urine tests may suggest that imaging tests are needed to look for craniopharyngioma. Imaging tests show pictures of the inside of the body. There are 2 main types of imaging tests used to find craniopharyngioma.

  • Computed tomography (CT or CAT) scan. A CT scan takes pictures of the brain using x-rays taken from different angles. A computer combines these pictures into a detailed, 3-dimensional image that shows abnormalities, including tumors. Sometimes, a special dye called a contrast medium is injected into a patient’s vein during the scan to provide better detail.

  • Magnetic resonance imaging (MRI). An MRI produces detailed images of the inside of the body using magnetic fields, not x-rays. An MRI can be used to measure the tumor’s size. Often, a special dye called a contrast medium is injected into a patient’s vein before the scan to create a clearer picture.

After diagnostic tests are done, your child’s doctor will review the results with you. This information will be used to recommend treatment options.

The next section in this guide is Stages. It explains that doctors do not commonly use stage to describe craniopharyngioma. Use the menu to choose a different section to read in this guide.