Brain cancer is the presence of an overgrowth of malignant cells in the brain which multiply uncontrollably. The cancer can be primary, forms directly in the brain cells; or metastatic (secondary), the tumor comes from elsewhere in the body and has migrated to the cerebral tissue. Metastatic brain cancers are much more common than primary tumors. They are always malignant; unlike primary which can be benign (non-cancerous). Several types of cancer can be responsible for the occurrence of a metastatic brain cancer: breast cancer, lung cancer, kidney cancer, colon cancer, and others.
Brain cancer develops within the skull, a bony structure which protects the brain and supports the structures of the face. As the tumor develops, it increases the intracranial pressure (intracranial hypertension) and compresses the functional areas of the brain. At the beginning, when the tumor is still small, it usually causes no symptoms. But the more it grows, symptoms may occur: headache, nausea and / or vomiting, convulsions, seizures … Please see brain cancer symptoms.
Types of Brain Tumor
The brain cancer treatment you receive depends on the type of tumor you have. In term tumoral, there are 2 main types of brain tumors:
Benign Tumors (not cancerous) – They develop quite slowly and usually remain isolated from neighboring cerebral tissue. They do not spread to other parts of the brain and are generally easier to be treated or removed surgically than malignant tumors. However, this article is about malignant brain tumor; let’s go back to it.
Malignant Tumors – a malignant brain tumor usually develops more rapidly than benign and tends to invade the surrounding tissue. In spite of advance in brain cancer treatment, it is often impossible to completely separate them from surrounding healthy tissue without causing serious damage.
Radiological tests such as magnetic resonance imaging (MRI) and computed tomography (“CT”), used to locate the tumor, are not enough to confirm if the condition is cancerous or not. A biopsy is essential to determine whether it is a benign or malignant tumor. There are many brain cancer types. It is therefore important, once the diagnosis is confirmed, to determine the exact type being diagnosed.
Types of Brain Cancer
Brain cancers are relatively rare, but often fatal, regardless of the type you are diagnosed with.
The most common brain tumors are malignant gliomas, in which some of the glial cells (also called neuroglial cells or supporting cells ‘in the central nervous system’) become cancerous. Among the gliomas include glioblastoma multiforme (GBM) and anaplastic astrocytoma. GBM is the most common of all gliomas. Glioblastoma multiforme and anaplastic astrocytoma tend to be aggressive and are fast-growing.
Oligodendroglioma, another type of glioma, and a rare brain cancer, occurs mainly in adults. Gliomas are responsible for up to 60% of all cases of brain tumor (malignant and benign), both in children and adults.
Medulloblastoma, which derives from the bulb spinal cells at the base of the brain, mainly in the section called in the cerebellum or posterior fossa, is the most common type of brain tumor in children. It occurs mostly before puberty.
Some other types of brain cancer include sarcoma and adenocarcinoma. They are extremely rare brain tumors. A very common form of adenocarcinoma is called adenoid cystic carcinoma. It usually starts in the sinonasal mucosa and invades the base of the skull. It tends to cause headaches and seizures. For more information on sarcoma, please visit the main article.
The brain, belonging to the central nervous system (CNS), contains about 100 billion neurons and has an average weight of 3 pounds (1300-1400 grams). It also contains glial cells and astrocytes, the supporting and neuroglial cells of the CNS. It is bathed in a clear, colorless bodily fluid called cerebrospinal fluid.
Located in the skull, the brain is the seat of higher (cognitive functions, sense, nerve responses) and vegetative (respiration, fluid circulation, reproduction, excretion, nutrition) functions. It is an essential organ that regulates all vital functions. The brain receives information from the entire body through afferent nerves, integrates and analyzes them, and then responds accordingly with new signals to the body parts affected by the efferent nerves.
The brain is thus responsible for the heart and respiratory rate, functions, which for us, are unconscious. But it is also involved in decision making, in body motion, behavior, memory, consciousness, and others.