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