| Brain Tumor | | | | location in the brain. Undifferentiated |
| | | | neuroectodermal tumors of the cerebellum have |
| A brain tumor - primary or secondary - can | | | | historically been referred to as |
| cause a variety of signs and symptoms because | | | | medulloblastomas, while tumors of identical |
| it can directly press on or invade brain | | | | histology in the pineal region would be |
| tissue. This can damage or destroy areas | | | | diagnosed as pineoblastomas. The nomenclature |
| responsible for sight, movement, balance, | | | | of pediatric brain tumors is controversial |
| speech, hearing, memory or behavior. Brain | | | | and potentially confusing. Some pathologists |
| tumor symptoms vary from patient to patient, | | | | advocate abandoning the traditional |
| and most of these symptoms can also be found | | | | morphologically-based classifications such as |
| in people who do NOT have brain tumors. | | | | medulloblastoma in favor of a terminology |
| | | | that relies more extensively on the |
| Therefore, the only sure way to tell if you | | | | phenotypic characteristics of the tumor. |
| have a brain tumor or not is to see your | | | | |
| doctor and get a brain scan. The growth of | | | | Primary Brain Tumor |
| abnormal cells in the tissues of the brain. | | | | |
| Brain tumors can be benign (non-cancerous) or | | | | Astrocytomas - these tumors arise from small, |
| malignantA primary brain tumor is a group | | | | star-shaped cells called astrocytes. They may |
| (mass) of abnormal cells that start in the | | | | grow anywhere in the brain or spinal cord. In |
| brain. This article focuses on primary brain | | | | adults, astrocytomas most often arise in the |
| tumors in adults. Brain tumors encompass | | | | cerebrum. In children, they occur in the |
| neoplasms that originate in the brain itself | | | | brain stem, the cerebrum and the cerebellum. |
| (primary brain tumors) or involve the brain | | | | A grade III astrocytoma is sometimes called |
| as a metastatic site. Brain tumors | | | | anaplastic astrocytoma. A grade IV |
| (metastatic brain tumors), which are | | | | astrocytoma is usually called glioblastoma |
| malignant, are more common. These tumors | | | | multiforme. |
| result from cancer that started elsewhere in | | | | |
| the body and spread (metastasized) to the | | | | Brain stem gliomas - These tumors occur in |
| brain. | | | | the lowest, stem-like part of the brain. The |
| | | | brain stem controls many vital functions. |
| Classification | | | | Most brain stem gliomas are high-grade |
| | | | astrocytomas. |
| HISTOPATHOLOGIC CLASSIFICATION - Primary | | | | |
| brain tumors are classified by light | | | | Secondary Brain Tumor |
| microscopy according to their predominant | | | | |
| cell type and graded based upon the presence | | | | Metastatic brain tumors originate from |
| or absence of standard pathologic features. | | | | malignant tumors located primarily in other |
| Historical attempts at developing a | | | | organs. Their incidence is higher than that |
| classification system for brain tumors date | | | | of primary brain tumors. The most frequent |
| back to the 1830s. The German pathologist | | | | types of metastatic brain tumors originate in |
| Rudolf Virchow first introduced the term | | | | the lung skin (malignant melanoma, kidney |
| "glioma" in 1860. Virchow was also the first | | | | (hypernephroma, breast (breast carcinoma), |
| to attempt a correlation of microscopic to | | | | and colon (colon carcinoma). These tumor |
| macroscopic features of CNS tumors. | | | | cells reach the brain via the blood-stream. |
| | | | |
| Cellular Classification-He classification of | | | | Some non-tumoral masses and lesions can mimic |
| brain tumors is based on both | | | | tumors of the central nervous system. |
| histopathological characteristics and | | | | |