The brain is not a homogeneous, or uniform, organ -- different parts of the brain govern different functions of the body, so symptoms of a brain tumor are usually related to the location of the tumor rather than to its size. Symptoms are caused by tissue destruction, compression of normal brain tissue by the tumor, swelling in the tissues around the tumor, or obstruction of the flow of fluid (called cerebrospinal fluid) that flows around the brain and spinal cord.
Because symptoms reflect the tumor's location, they can sometimes indicate where the tumor is located and what type of tumor it is. Symptoms of brain tumors (which are often the same symptoms for brain metastases) include:
- headache (when a tumor presses on surrounding brain tissue)
- nausea and vomiting
- seizures (when a tumor irritates the normal brain)
- speech problems, impaired vision, weakness in parts of the body and trouble walking, problems of understanding (when a tumor affects these functional areas of the brain)
Symptoms of spinal cord cancers include:
- pain or numbness (when a tumor triggers or blocks circuits that carry sensation signals from nerves to the brain)
- motor problems (when a tumor disrupts the normal flow of signals from the brain to the muscles)
- difficulty controlling bowel and/or bladder function
Because symptoms produced by a central nervous system tumor often resemble the symptoms of other diseases, careful evaluation and diagnosis are critical to determine the cause of these symptoms.
