Brain Tumor Glossary of Terms

Easily explore the meaning of hundreds of medical terms or words, many directly used in brain tumor-related terminology.

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A-V Malformation

A haemangioma or arteriovenous malformation is a tangle of abnormal vessels that forms an abnormal communication between the arterial and venous systems. Most are developmental (congenital). If large enough, they may produce a shunt of sufficient magnitude to raise the cardiac output. AVM's may occur in the brain, brainstem and spinal cord, where they may cause headaches, seizures or bleeding (subarachnoid hemorrhage).

Accelerated Radiation Therapy

Radiation treatment in which the total dose of radiation is given over a shorter period of time (fewer days) compared to standard radiation therapy.

Accelerated-fraction Radiation Therapy

Radiation treatment in which the total dose of radiation is divided into small doses and the treatments are given more than once a day. The total dose of radiation is also given over a shorter period of time (fewer days) compared to standard radiation therapy.

Acoustic Neuroma

A progressively enlarging, benign tumor, usually within the internal auditory canal. Symptoms, which vary with size and location of the tumor, may include hearing loss, headache, disturbances of balance and gait, facial numbness or pain and tinnitus.

Adenocarcinoma

A cancer that originates in glandular tissue.

Adenoma

A benign tumor of a glandular structure or of glandular origin.

Adenomyoma

A benign tumor composed of muscular and glandular elements

Adjuvant

A treatment used in addition to or accompanying another treatment.

Advanced Cancer

Cancer that has spread to other places in the body and usually cannot be cured or controlled with treatment.

Advanced Directive

A legal document that states the treatment or care a person wishes to receive or not receive if he or she becomes unable to make medical decisions (for example, due to being unconscious or in a coma). Some types of advance directives are living wills and do not resuscitate (DNR) orders.

Adverse Effect

An unexpected medical problem that happens during treatment with a drug or other therapy. Adverse effects do not have to be caused by the drug or therapy, and they may be mild, moderate, or severe. Also called adverse event.

Adverse Event

An unexpected medical problem that happens during treatment with a drug or other therapy. Adverse events do not have to be caused by the drug or therapy, and they may be mild, moderate, or severe. Also called adverse effect.

Amygdala

Amygdala are almond-shaped groups of neurons located deep within the medial temporal lobes of the brain. Shown in research to perform a primary role in the processing and memory of emotional reactions, the amygdalae are considered part of the limbic system.

Analgesics

A drug or medicine given to reduce pain without resulting in loss of consciousness. Analgesics are sometimes referred to as painkiller medications. There are many different types of analgesic medications available in both prescription and over-the-counter preparations. Examples of analgesic drugs include aspirin, acetaminophen (Tylenol), ibuprofen (Motrin, Advil), naproxen (Aleve, Naprosyn), the COX-2 inhibitor celecoxib, and narcotic drugs including morphine, oxycodone, and hydrocodone (Vicodin). Analgesics may also be combined with other drugs in some types of medications (for example, analgesics are combined with decongestants and/or antihistamine in many over-the-counter cold remedies).

Anaplastic

A term used to describe cancer cells that divide rapidly and have little or no resemblance to normal cells.

Anti-angiogenesis

Anti-angiogenesis drugs: These drugs, which include angiostatin and Endostatin, halt the process of developing new blood vessels (angiogenesis). Angiostatin is a piece of a larger and very common protein, plasminogen, that the body uses in blood clotting. Endostatin is a piece of a different protein, collagen 18, that is in all blood vessels. Both angiostatin and Endostatin are normally secreted by tumors. It is hoped that they will provide the basis for a new class of agents to treat cancer.

Anticancer Therapy

Treatment to stop or prevent cancer.

Anticarcinogenic

Having to do with preventing or delaying the development of cancer.

Astrocytes

a star-shaped cell; esp : any comparatively large much-branched neuroglial cell

Astrocytoma

Astrocytes, which can develop in any part of the brain or spinal cord, are star-shaped glial cells where the tumor originates. It can be any grade, but in adults, it most often arises in the cerebrum. More than 75 percent of all gliomas are astrocytomas. Commonly astrocytomas are classified in four grades:

* Grade I astrocytoma:
* Called low-grade glioma
* Slow growing
* Well-defined borders
* Rare and almost exclusively found in children or teens

* Grade II astrocytoma:
* Rarely spreads to other parts of central nervous system
* Slow growing
* Borders not defined
* Common among men and women, 20s to 50s

* Grade III astrocytoma:
* Sometimes called a high-grade or an anaplastic astrocytoma
* More aggressive than grade II astrocytoma
* Cells not uniform
* Invades other tissue
* More common in men than women

* Grade IV astrocytoma:
* Called a glioblastoma or malignant astrocytic glioma
* Most invasive type of glial tumor
* Composed of several different cells, making it difficult to treat
* Grows rapidly and invades other tissue
* May have evolved from low-grade tumor
* Common in young adults and among men and women, 50s to 70s
* Account for 30 percent of all primary brain tumors
* More common in men

Astrocytoma, which account for 3,000 new cases a year in the U.S., is the most common form of brain cancer. It represents 23 percent of primary brain tumors. The annual U.S. incidence rate: three per 100,000.

Avastin

A drug used to treat several types of cancer, including certain types of colorectal, lung, and breast cancers and glioblastoma. It is also being studied in the treatment of other types of cancer. Avastin binds to vascular endothelial growth factor (VEGF) and may prevent the growth of new blood vessels that tumors need to grow. It is a type of antiangiogenesis agent and a type of monoclonal antibody. Also called bevacizumab.