Brain Tumors

A brain tumor is a mass of abnormal cells that grow in the brain. Brain tumors can be benign (non-cancerous) or malignant (cancerous) and can start anywhere in the brain. Malignant tumors grow rapidly, while benign brain tumors tend to grow more slowly. Though benign tumors are generally less worrisome when they occur in other parts of the body, in the brain, they often grow large enough to disrupt normal functioning. If they do, surgery is required.

    Key Terms

    Frequently Asked Questions

    • What are the symptoms of a brain tumor?

      Seizures and severe headaches are usually the first sign a brain tumor might be present. Other symptoms can include cognitive changes, loss of consciousness, and dizziness. Brain tumors can also present with weakness or numbness in just one part of the body. Headaches that are tumor-related are generally unusually severe or will be combined with other symptoms, such as vomiting or fever.

    • How do you know if you have a brain tumor?

      Symptoms of a brain tumor may be mild and subtle or severe and life-threatening, and are usually related to impairment in the area of the brain where the tumor is located. Only a full medical evaluation can determine whether a brain tumor is causing your neurological or other symptoms, which may also be caused by many other conditions.

    • How long does it take for brain tumor symptoms to appear?

      Tumors can grow rapidly or be slow-growing. Tumors are classified according to grades (numbered I to IV) that rank how quickly they grow and spread to other tissues. Tumors called gliomas, which start in glial brain cells, make up more than three-quarters of malignant, quickly growing brain tumors. However, only about a third of brain tumors are gliomas.

    Page Sources
    Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
    1. American Association of Neurological Surgeons. Brain tumors.

    2. American Cancer Society. Types of brain and spinal cord tumors in adults.