Basic Facts on Brain Tumors

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If you have been diagnosed with a brain tumor, know someone who has, ordered a workup from your doctor to "check for a brain tumor," or are just curious about what exactly brain cancer is, then this question-answer style format will hopefully help you in comprehending this complex topic.

What is a Tumor?

There are trillions of cells in the body. Cancer cells are grown abnormally and in an uncontrolled manner to form a tumor.

  A tumor can invade or grown into and replace healthy tissue in our body.

What is a Brain Tumor?

A brain tumor occurs when cells in the brain grow out of control and in an abnormal way. There are different types of brain cancer, and they grow at different rates, some slowly, and some rapidly.

Tumors can be malignant (cancerous) or benign (non-cancerous). This article focuses on brain cancer or malignant tumors.

Where Does Brain Cancer Come From?

Brain cancer arises from cells within the central nervous system (CNS) or from tumors elsewhere in the body that have spread or metastasized to the central nervous system.

What are the Symptoms of a Brain Tumor?

The symptoms of a brain tumor are variable based on a number of factors like the size and location of the tumor. In addition, it's important to understand that most of these symptoms (especially headaches) are likely not a sign of a brain tumor.

This is why it's best to see your doctor if you are concerned, as the diagnosis is complex and requires a careful evaluation by a healthcare professional.

That being said, potential symptoms of a brain tumor include one or more of the following:

  • Memory Loss
  • Mood Disturbances (i.e. Depression) and/or Personality Changes
  • Muscle Weakness
  • Difficulty with Language (i.e. slurred speech)
  • Vision Problems

How Do Brain Tumors Produce Symptoms?

Brain tumors produce the above symptoms through three main ways:

  • Cancer cells invade and replace healthy tissue. For instance, brain tissue that is normally used to help you communicate is invaded by cancer cells, causing difficulty saying words -- this is called dysarthria.
  • Compression of adjacent structures in the brain. For instance, compression of the optic nerve, which connects your retina to your brain, can lead to vision alterations.
  • Increased Intracranial Pressure: A brain tumor takes up space and increases pressure around your brain. A doctor can detect this by looking into your eyes with an ophthalmoscope and seeing papilledema, a condition characterized by optic disc swelling of the eye.

How is Brain Cancer Detected?

If your doctor suspects a brain tumor, he will order an imaging test of the brain, such as a CT scan or an MRI. If the imaging test reveals a concerning mass, then you will be referred to a neurosurgeon. The neurosurgeon will perform a possible biopsy and/or surgery for resection or removal of the tumor.

Often times, the biopsy is done at the same time as the surgery. With a tissue biopsy, the surgeon takes a tiny sample of brain tissue from the concerning mass. The tissue is examined by a pathologist under the microscope to see if any cancer is present and if so, the type of cancer.

What are the Different Types of Brain Cancer?

Brain tumors can be primary or metastatic. A primary brain tumor originates in the brain. A metastatic tumor means that the cancer is coming from some other part of the body. For example, metastatic breast cancer to the brain means that an individual has breast cancer that has spread to the brain.

Approximately 20 to 40 percent pf patients with cancer develop metastatic brain cancer. For individuals with primary brain tumors, their cancer originates in the brain. Metastatic brain cancer is more common than a primary brain tumor.

How Do Brain Tumors Develop?

Experts simply do not know. Most are spontaneous. Some may be the result of genetic diseases (neurofibromatosis, tuberous sclerosis) or from exposure to radiation or carcinogens.

Are Brain Tumors Contagious?

Rest assured. Brain tumors are not contagious.

How Do You Treat a Brain Tumor?

It depends on the type of brain cancer you have in addition to your overall health and wishes. Treatment ranges from surgery (removal of the whole tumor or parts of the tumor), radiation to the brain, and chemotherapy.


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National Institute of Neurological Disorders and Stroke. NNDS Brain and Spinal Tumor Information Page.

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