Diagnosis

At Mayo Clinic, your subspecialized care team of brain tumor experts will take the time to listen to you, have conversations and answer questions in order to accurately diagnose your condition and tailor the best treatment options to you. This begins with a thorough evaluation to review your symptoms and medical history and coordinate all necessary tests and imaging. This comprehensive evaluation may be overwhelming, but your Mayo Clinic care team will take as much time as necessary to explain, interpret and guide you through the process. Your evaluation may include:

  • A neurological exam. A neurological exam may include, among other things, checking your vision, hearing, balance, coordination and reflexes. Difficulty in one or more areas may provide clues about the part of your brain that could be affected by a brain tumor.
  • Imaging tests. Magnetic resonance imaging (MRI) is commonly used to help diagnose brain tumors. In some cases a dye may be injected through a vein in your arm before your MRI.

    A number of specialized MRI scans — including functional MRI, perfusion MRI and magnetic resonance spectroscopy — may help your doctor evaluate the tumor and plan treatment.

    Other imaging tests may include computerized tomography (CT) scan and positron emission tomography (PET).

  • Tests to find cancer in other parts of your body. If it's suspected that your brain tumor may be a result of cancer that has spread from another area of your body, your doctor may recommend tests and procedures to determine where the cancer originated. One example might be a CT scan of the chest to look for signs of lung cancer.
  • Collecting and testing a sample of abnormal tissue (biopsy). A biopsy can be performed as part of an operation to remove the brain tumor, or a biopsy can be performed using a needle.

    A stereotactic needle biopsy may be done for brain tumors in hard to reach areas or very sensitive areas within your brain that might be damaged by a more extensive operation. Your neurosurgeon drills a small hole into your skull. A thin needle is then inserted through the hole. Tissue is removed using the needle, which is frequently guided by CT or MRI scanning.

    The biopsy sample is then viewed under a microscope to determine the specific nature of the tumor and to guide future treatment decisions.

  • Molecular diagnosis. Recent research has shown that specialized genetic testing of a brain tumor is essential for diagnosis, prognosis and treatment decisions. Experts at Mayo Clinic are leaders in this field, and are able to bring the latest insights from this rapidly evolving science to clinic where the best possible treatment decisions for your particular situation can be offered.

    Mayo Clinic subspecialized experts conduct these tests and collaborate with each other on a daily basis and at team conferences to provide accurate and timely diagnoses and treatment strategies individualized for each patient. What might take months to accomplish elsewhere can typically be done in only a matter of days at Mayo Clinic.