What is a brain tumor?
A tumor develops when the body’s cells multiply when they are not needed. A brain tumor is a mass of unnecessary or abnormal cells that grow in the brain.

What is the difference between malignant and benign brain tumors?
Malignant brain tumors contain cancer cells. They can grow very quickly, invade and destroy healthy tissues, and may spread to other areas of the brain.  Slower growing brain tumors or tumors that do not contain cancer cells may be referred to as “benign” or“non-malignant.”  However, because the brain is inside the hard skull, there is no room for abnormal growths of cells.  Malignant and benign brain tumors can both be life threatening and often require the same treatments.

What is the difference between primary and metastatic brain tumors?
A tumor that starts growing in the brain is a primary brain tumor. These tumors may spread within the brain, but rarely travel to other sites in the body. Metastatic brain tumors are formed from cancer cells that originate in other parts of the body and travel to the brain to form tumors. Cancers of the lung, breast, colon, and melanoma often spread to the brain.

What are the different kinds of brain tumors?
There are many different kinds of brain tumors and names for brain tumors. These names will often reflect the location of the tumor, the kinds of cells in the tumor, and the tumor’s level of aggressiveness. Scientists use the appearance of the tumor cells under a microscope to determine the kind of tumor. Tumors are also given a grade indicating the degree of malignancy. Grade 1 tumors are the slow growers and are often considered non-malignant or benign. The most malignant tumors are given a grade of IV. This web- site provides links to many other sites that provide detailed information on all tumor types.

What is the cause of brain tumors?
Unfortunately, the cause of brain tumors is unknown. Just as there are many kinds of brain tumors, there may be just as many causes. There is likely a combination of factors. One thing known for sure is that brain tumors are not contagious. About 5% of primary brain tumors can be associated with hereditary factors. The cause of the remaining 95% of brain tumors is studied by scientists the world over. Progress in determining causes and improving treatment is aided by statistics on brain tumor occurrence gathered at all major medical facilities.

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