A brain tumor or intracranial neoplasm occurs when abnormal cells form within the brain. There are two main types of tumors: malignant or cancerous tumors and benign tumors.Cancerous tumors can be divided into primary tumors that start within the brain, and secondary tumors that have spread from somewhere else, known as brain metastasis tumors. This article deals mainly with tumors that start within the brain. All types of brain tumors may produce symptoms that vary depending on the part of the brain involved
Symptoms as consequences of increased intracranial pressure (often first noticed) Large tumors or tumors with extensive peritumoral swelling (edema) inevitably lead to elevated intracranial pressure which translates clinically into headaches, vomiting (with or without nausea), altered state of consciousness (somnolence, coma), dilation of the pupil on the side of the lesion (anisocoria), papilledema (prominent optic disc at the funduscopic eye examination). However, even small tumors obstructing the passage of cerebrospinal fluid (CSF) can also present such symptoms. Increased intracranial pressure may result in brain herniation (i.e. displacement) of certain parts of the brain, such as the cerebellar tonsils or the temporal uncus, resulting in lethal brainstem compression. In very young children, elevated intracranial pressure may cause an increase in the diameter of the skull and bulging of the fontanelles.
New techniques for imaging scans are being researched. These may help doctors better track how well treatment is working and watch for possible tumor recurrence or growth.Researchers are examining biomarkers to find better ways of using blood or other tests to determine the presence of a brain tumor before symptoms begin. Immunotherapy, also called biological response modifier (BRM) therapy, is designed to boost the body's natural defenses to fight the cancer. It uses materials either made by the body or in a laboratory to improve, target, or restore immune system function. Different methods are being studied for brain tumors, such as the use of dendritic cells or the use of vaccines aimed against a specific molecule on the surface of the tumor cells. Several methods are currently being tested in clinical trials.
A total of 1755 incident cases of brain and other CNS cancer were identified among the 19,059,262 person-years covered by the registry from 1973 to 2008, which 996 occurred in men and 759 in women. In Table 1, the number of cases, person-years, age-standardized rates (ASR) and rates ratios are provided splitted by period (1973-1990 and 1991-2008), gender, area (urban and non-urban), and age-group. Annual percentage of change of rates and the corresponding CI-95% are also provided for the entire period. Overall, ASR increased from 6.461 to 7.033 cases per 100,000 person-years between 1973-1990 and 1991-2008. By gender, ASRs changed from 8.281 to 8.156 in male while in female rate increased from 4.790 to 5.923 between the periods mentioned before. By area, higher rates were observed in urban than non-urban areas during the entire period corresponding to an ASR ratio between urban and non-urban areas of 1.236 (CI95% 1.236-1.237) in 1973-1990 and, 1.126 (CI95% 1.125-1.126) in 1991-2008.