Medical Terms & Definitions Every Brain Tumor Patient Should Know

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Cerebrospinal fluid
A watery fluid that is continuously produced and absorbed within the brain and also around the surface of the brain and spinal cord.

Cerebrum
The largest part of the brain. It is divided into two hemispheres, or halves.

Chemotherapy
Treatment of cancer with powerful medications that prevent cancer cells from dividing and growing.  This can have the effect of shrinking existing tumors, or preventing stray tumor cells from developing into larger tumors.  Because chemotherapy agents are such powerful medications, they are often accompanied by moderate to severe side effects: nausea, hair loss, brain fog, tiredness, weakened immune system, etc.

Clinical trials
Trials to evaluate the effectiveness and safety of medications or medical devices by monitoring their effects on large groups of people.  In cancer patients, a new medication or device is tested among people with a similar diagnosis to see how it compares to current therapies or “standard of care” in terms of effectiveness.

Coagulation
In medicine, the clotting of blood. The process by which the blood clots to form solid masses, or clots.

Congenital
A condition that is present at birth, and often runs in families.

Craniotomy
A surgical operation in which an opening is made in the skull (cranium) to allow surgery to be performed on the brain. This differs from a crainectomy, in which a portion of the skull is removed to allow injured/swollen brain tissue room to expand.

CT or CAT scan
(Abbreviation for computed tomography scan) A type of computer-assisted X-ray technology that produces detailed, multidimensional images of internal organs. CT imaging is sometimes compared to looking into a loaf of bread by cutting the loaf into thin slices. When the image slices are reassembled by computer software, the result is a very detailed multidimensional view of the body’s interior.  CT imaging is often used in the diagnosis of cancer since it allows a physician to confirm the presence of a tumor and measure its size, precise location, and the extent of the tumor’s involvement with other nearby tissue.

CyberKnife and Gamma Knife
A non-invasive surgery procedure destroys tumors w/out the risks of traditional surgery, through using radiation to destroy tumor cells.  Unlike invasive surgery, patients treated usually are able to return to their normal activities sooner.

Drain
A device for removing fluid from a cavity or wound. A drain is typically a tube attached to some sort of holding container.

Genome
A genome is a comprised of a complete set of DNA and all of genes it contains. Each genome contains all of the information needed to build and maintain a person’s cells from the beginning to the end of their lives. In humans, there are more than 3 billion DNA base pairs.

Genomic sequencing
With new technologies, it is now possible to identify areas within a person’s DNA where changes (or genetic mutations) have taken place, including those that could cause abnormal cell growth or cancer.  This enables precise targeting of therapies, or personalized medicine, where treatments are tailored to a person’s unique genetic profile, as opposed to being based on clinical signs and symptoms.

Grade
Grade is used to describe how abnormal the tumor cells look under a microscope. Grade 1 cells are quite similar to normal cells and tissue; in Grade 2, there is a fair degree of difference. Grade 3 or 4 cells bear the least resemblance to normal cells and tissue. Typically Grade 3 or 4 cells are extremely aggressive and signify a rapidly-growing tumor.

Hospice care
Care designed to give supportive care to people in the final phase of an illness and focus on comfort and quality of life, rather than cure.  The goal is for patients to be comfortable and free from pain.

Immune system
A complex system that is responsible for protecting their body against infections and foreign substances.

Incision
A cut through skin or other tissue as part of a medical procedure.

Inflammation
A localized reaction that produces redness, warmth, swelling, and pain as a result of infection, irritation, or injury. Inflammation can be external or internal.

Intracranial
Within the skull, the bony dome that houses and protects the brain.

Lesion
An area of abnormal tissue change. Lesions vary in severity from harmless to serious.

Lymphatic system
The tissues and organs, including the bone marrow, spleen, thymus, and lymph nodes (all located outside the brain), that produce and store cells that fight infection and disease. The channels that carry lymphatic fluid are also part of this system.

Malignant
A term for diseases in which abnormal cells divide without control and often invade nearby tissues. Malignant (cancer) cells can also spread to other parts of the body

Medical Devices
Medical devices are an emerging and exciting technology in the treatment of GBM. Currently, the only one which the FDA has approved is Optune. Optune delivers TTF fields, frequency specific, low intensity fields which interfere with cell division to fight and stop tumor growth.

Metastasis
Metastasis is a complex process where a tumor or cancer spreads to distant parts of the body from its original site. The majority of brain tumors originate in another part of the body such as the lung, breast or colon and then spread to the brain.

Magnetic resonance imaging (MRI):
A procedure in which radio waves and a powerful magnet linked to a computer are used to create detailed picture of areas inside the body. These pictures can show the difference between normal and diseased tissue.

Neurosurgeon
A physician who specializes in surgery on the brain and other parts of the nervous system.

Neuro-oncologist
An oncologist who specializes in tumors of the brain and other parts of the nervous system.

Oncologist
A physician who specializes in the diagnosis and treatment of cancer. After a cancer diagnosis is made, it is the oncologist’s role to explain the cancer diagnosis and the meaning of the disease stage to the patient; discuss various treatment options; recommend the best course of treatment; deliver optimal care; and improve quality of life.

Onset
In medicine, the first appearance of the signs or symptoms of an illness as, for example, the onset of a cold or influenza (when the person starts to ache, cough, or feel sneezy).

Papilloma
A small solid benign tumor with a clear-cut border that projects above the surrounding tissue. A raised wart is an example of a papilloma.

Parietal lobe
Part of the brain, specifically the section of the cerebral hemisphere that lies beneath the parietal bone, the main side bone of the skull.

Pathologist
A physician who identifies diseases and conditions by studying cells and tissues, most commonly a microscope. This identification is a critical step in diagnosis and treatment of any type of cancer.

Personalized medicine
Any type of treatment specifically tailored to the individual patient (as opposed to the physical characteristics of the disease), most commonly used to describe treatments based on the patient’s unique genetic profile.

Physical therapist
A person who is trained and certified by a state or accrediting body to design and implement programs that rebuild a patient’s physical function including, strength, stamina, flexibility and balance.

Prognosis
The forecast of the most likely course of a disease and outcome; the patient’s chance of recovery.  This is based on what happened to other patients with a similar diagnosis, the treatments selected, and other factors such as the patient’s general health.

Quality of Life
The patient’s ability to enjoy normal life activities. Quality of life is an important consideration in medical care as some medical treatments can seriously impair quality of life without providing appreciable benefit, whereas others greatly enhance quality of life.

Radiation Therapy Radiotherapy
The treatment of disease with ionizing radiation. In radiation therapy, high-energy rays are often used to damage cancer cells and stop them from growing and dividing. A specialist in the radiation treatment of cancer is called a radiation oncologist. Stereotactic radiosurgery (SRS) and hypofractionated stereotactic radiotherapy (HFSRT) have become important treatments for brain tumors.

Resection
Surgical removal of part of an organ or tumor.

Rule out
Term used in medicine, meaning to eliminate or exclude something from consideration.

Shunt
Hole or small tube which moves, or allows movement of fluid from one part of the body to another. In brain tumor patients, a shunt is used to prevent buildup of fluid in the brain.

Stage
Stage is based on our knowledge of how cancer typically progresses and provides a common language for describing the severity of a person’s cancer based on the size and/or extent of the original tumor and whether or not cancer has spread in the body. Staging is important for planning the most appropriate treatment, estimating prognosis, and identifying clinical trials that might be helpful.

Stereotactic
One of a large group of chemical substances classified by a specific carbon structure. Steroids include drugs used to relieve swelling and inflammation, such as dexamethasone, prednisone and cortisone, and some sex hormones, such as testosterone and estradiol.

Survivor
Anyone who is either currently undergoing treatment for cancer or has done so in the past.  With new treatment options, more and more people are cured or living a very long time following a diagnosis of cancer. “Survivorship” is increasingly becoming an area of focus to help these patients with the numerous physical, psychological, social, spiritual and financial issues often faced during and after active treatment.

Symptom
Anything out of the normal, in function, appearance, or sensation, experienced by the patient.  Symptoms can be caused by the disease itself or side effects of treatment.

Therapy
The treatment of disease. Therapy is synonymous with treatment.

Trauma
Refers to either an emotional shock or severe body injury, either from the impact of a life-changing event such as a cancer diagnosis, or a physical injury resulting from a fall or surgery.

Tumor (or neoplasm)
An abnormal mass of tissue. Tumors can be benign or malignant (cancerous). They may be solid or fluid-filled. A tumor does not  always mean cancer – tumors can be benign (not cancerous), pre-malignant (pre-cancerous), or malignant (cancerous). Their specific names usually reflect their shape and part of the body where they appear (for example, a brain tumor occurs in the brain, and is comprised of brain tissue).

Vascular
Having to do with blood vessels including all of veins and arteries.

Vestibular
Having to do with a structure that is a vestibule (entrance), such as the vestibule of the ear. Having to do with the body’s system for maintaining equilibrium.

X-Ray
High-energy radiation with waves shorter than those of visible light. X-ray is used in low doses to make images that help to diagnose diseases and in high doses to treat cancer.

Different Types of Brain Tumors

Following are definitions for the most common types of brain tumors.  Although there are more than 120 different types of brain tumors, these account for more than 90% of all diagnoses.

Adenoma
A benign tumor that arises in or resembles glandular tissue. If an adenoma becomes cancerous, it is called an Adenocarcinoma.

Astrocytoma
A tumor that begins in the brain or spinal cord in small, star-shaped cells called astrocytes. The location of the tumor depends on the age of the person. In adults, astrocytomas most often arise in the cerebrum, and temporal lobes whereas in children, they may arise in the brain stem, cerebrum, and cerebellum.

Ependymoma
A type of brain tumor that derives from the glial cells that line the cavities within the brain’s ventricles. Because cerebrospinal fluid normally flows through these ventricles, blockage due to an ependymoma can cause buildup of fluid, pressure on the brain, swelling of tissues.

Glioblastoma multiforme (GBM)
A fast-growing type of astrocytoma that forms from glial (supportive) tissue of the brain and spinal cord and has cells that look very different from normal cells. Glioblastoma multiforme usually occurs in adults and affects the brain more often than the spinal cord. Also called GBM, glioblastoma, and grade IV astrocytoma.

Glioma
A brain tumor that begins in a glial, or supportive cell, in the brain or spinal cord. Malignant gliomas are the most common primary tumors of the central nervous system (the brain and spinal cord). They are often resistant to treatment and carry an unfavorable prognosis.

Medulloblastoma
A type of brain tumor that tends to occur in children, arise in the cerebellum (in the lower part of the brain), and spread along the spine. Medulloblastoma is the most common type of primary brain tumor in childhood. Medulloblastomas occasionally metastasize outside the central nervous system.

Meningioma
A common type of slow-growing, usually benign brain tumor that arises from the membranes covering the brain and spinal cord. They tend to occur in people between ages 40 and 60 but can occur at any age. A person may have several meningiomas. Very rarely do meningiomas become malignant. Treatment ranges from observation to surgery.

Oligodendroglioma
A slow-growing brain tumor that usually occurs in young adults. These tumors are frequently located within the frontal, temporal or parietal lobes and cause seizures in a relatively high percentage of patients. Many oligodendrogliomas contain little specks of calcium (bone) and can easily bleed.

Pituitary adenoma
A benign tumor of the pituitary, the master gland that controls other glands and influences numerous body functions including growth. Although the tumor itself is not cancerous, it may affect pituitary function, and therefore may need to be removed.