A brain tumor is a new growth of tissue in the brain in which cell multiplication is uncontrolled and progressive. It grows independent of surrounding structures and has no physiological use. Brain tumors in children are typically primary tumors; that is, the tumor originates at the site rather than having migrated from another organ (e.g., metastases from the lung such as seen in adults with brain- tumors). Tumors may be classified as benign or malignant, and benign tumors have a better prognosis than do malignant tumors (i.e., they are unlikely to reoccur or to be progressive and fatal). Malignant tumors are given a grade of one to four, with one being the least malignant. Grades 1 and 2 are often called low-grade tumors, whereas Grades 3 and 4 are high-grade tumors. Brain tumors have serious consequences as they grow and crowd out or deplete oxy¬ gen and nutrient supply for normal cell growth. Brain tumors also put pressure on surrounding tissue that cuts off blood supply and flow of cerebrospinal fluid (CSF). In creased pressure and decreased blood supply often result in the death of surrounding tissue and in greater space for tumor growth.
A tumor that occurs in or around the brain, either malignant or benign. Among children, primary brain tumors, which originate in the brain itself, are most common, and they are the second most common cause of cancer death in children under 15 years old. Less common are secondary brain tumors, which arise from malignant cells originating elsewhere.
Tumor, often malignant, of brain tissue. Several types can occur. Symptoms include headache, visual disturbances, dizziness, loss of balance, nausea, and vomiting. Pain is not commonly present. Treatment involves surgery, chemotherapy, radiation therapy, or a combination.
An abnormal growth of tissue found inside the skull.
An inexact term to describe any intracranial mass — neoplastic, cystic, inflammatory (abscess), or syphilitic.