Neuro-Oncology University of Washington Medical Center

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About Brain Tumors: Symptoms Brain tumors cause symptoms in several ways. A tumor, also referred to as a mass, takes up space within the skull. As the tumor grows, because the skull is a rigid container, it does not "give" in order to allow for expansion. Therefore, it can cause an increase in pressure within the brain. This increase in pressure may cause some general symptoms. These are symptoms which occur regardless of the location of the tumor and may include headache, blurred vision, vomiting, confusion, and/or drowsiness. Other symptoms are "focal" symptoms. The type of focal symptom an individual may experience depends upon the location of the tumor. A tumor causes focal symptoms by exerting pressure on various brain structures and thereby interfering with the transmission of information (nerve impulses) to and from the involved area of the brain. Examples of focal symptoms include language comprehension or speech difficulties associated with the dominant temporal lobe, usually the left temporal lobe - especially in right-handed persons, or a weakness in a limb opposite the side of the tumor if the tumor is located in the motor cortex or its pathways, the nerve fibers. For a summary of the functions associated with various areas of the brain and for illustrations demonstrating the various brain areas see "A Primer of Brain Tumors", published by the American Brain Tumor Association. Seizures, in patients who have a brain tumor, are focal symptoms. The type of seizure depends upon what area of the brain is involved and to what brain areas the seizure activity spreads. For additional information on seizures, please refer to our seizures section. General symptoms may improve when the increased pressure within the brain is relieved by surgery and other treatments. Focal symptoms can improve if brain cells have not been permanently damaged by the tumor and its effects. Brain Edema When a mass is present in the brain, it can interfere with the blood supply to, and drainage from, the brain. When this happens, tissue fluid accumulates around the mass resulting in swelling. This fluid, together with the tumor mass, acts as an even larger mass, causing a "mass-effect". The fluid surrounding the mass is called edema. It can be treated by a variety of methods, most commonly with the steroid medication, Decadron (Dexamethasone) which decreases brain swelling (edema). Both general and focal symptoms which have been caused by brain edema, may improve when Decadron is taken.  Top of Page   |   Next Page