Although many brain tumors are popularly known as brain tumors, brain tumors are not all are cancerous. Cancer is a term reserved for malignant tumors.
Malignant tumors grow and spread aggressively, overpowering healthy cells by taking their space, blood and nutrients. Like all body cells, cancer cells need blood and nutrients to survive. This is particularly a problem in the brain due to increased growth to the limits of the skull can lead to increased intracranial pressure or distortion of vital surrounding structures, causing them to malfunction.
The tumors that grow aggressively are called benign. Almost all cancers that start with the brain do not spread to other parts of the body. The main difference between benign and malignant tumors is that malignant tumors can invade the brain tissue and grow rapidly. This rapid growth of the borders of the skull can rapidly cause damage to surrounding brain tissue.
In general, benign tumors is less serious than a malignant tumor. However, even benign tumors can cause many problems in the brain, but usually the problems progressed more slowly than malignant tumors.
Sometimes people confuse cerebral aneurysms with brain tumors. Cerebral aneurysms are tumors are the areas of arteries or veins of the brain are abnormally low and extend to form a ball or the expansion of the vessel wall. Rarely causes symptoms unless they begin to leak blood into the surrounding brain tissue. Aneurysms can be congenital (from birth) or extended or formed in the vessels of the brain after an injury to the vessel (eg, trauma, atherosclerosis, hypertension), but are not formed from cancer cells. Unfortunately, when the aneurysm produces symptoms that may resemble those produced by brain tumors.
Primary brain tumors
The brain consists of different types of cells and tumors that arise from cells of the brain of a type known as primary brain tumors.
Cancers occur when one type of cell changes and loses its normal characteristics. Once transformed, the cells grow and multiply abnormally.
As these abnormal cells grow, they become a mass of cells or a tumor.
Brain tumors caused by this transformation and abnormal growth of brain cells called primary brain tumors because they originate in the brain.
The tumors are the most common primary brain gliomas, meningiomas, pituitary adenomas, vestibular schwannomas, CNS lymphomas and primitive neuroendocrine tumors (medulloblastoma). Glioma is a broad term that includes many subtypes, including astrocytomas, oligodendrogliomas, ependymomas, choroid plexus papillomas and.
These primary tumors are named for the type of brain cells or brain from which they arise.
The brain tumors vary in their growth and ability to cause symptoms. The cells are rapidly growing, aggressive tumors usually show an abnormal microscopic. The National Cancer Institute (NCI) uses the classification system for classifying tumors. NCI lists the following degrees:
Grade I: The tissue is benign. The cells seem almost like normal brain cells, and cell growth is slow.
Grade II: The tissue is malignant. The cells look less like normal cells with cells from a tumor grade I.
Grade III: The malignant tissue has cells that look very different from normal cells. The abnormal cells are growing. These anomalies occur in cells called anaplastic.
Grade IV malignant tissue has cells that resemble the most unusual and tend to grow very quickly.
United States, are primary brain tumors and other cancers of the nervous system are estimated to develop in about 22,000 people in 2010, according to the National Cancer Institute.
Metastatic brain tumors
Metastatic brain tumors are made of cancer cells that spread through blood from a tumor located elsewhere in the body. The most common cancers that spread in the brain are those caused by cancer that starts in the lung, breast and kidney cancer and malignant melanoma, a skin cancer. The cells spread to the brain from another tumor in a process called metastasis. The process of metastasis occurs when cancer cells leave the primary cancer tissue and enter the lymphatic system is to reach the blood or the blood directly. These cancer cells eventually reach the brain tissue through the bloodstream, where they develop into tumors.
Metastatic brain tumors are the most common type of tumor in the brain and are much more common than primary brain tumors. Metastatic tumors are usually named after the type of tissue from which cancer cells home took place (for example, lung metastases or metastatic breast cancer). Brain blood flow usually determines how metastatic cancer cells will lodge in the brain, approximately 85% located in the brain (the largest part of the brain, located at the top of the cavity of the skull.) Unfortunately, most Metastatic brain tumors occur in more than one place in the brain tissue.
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