Glossary

1

• 1p19q

  A chromosome. If the chromosome 1p19q is showing deletion from an oligodendroglioma it means that the tumour is more responsive to chemotherapy.

A

• Adjuvant

  Usually used as ‘adjuvant therapies’. These are treatments which are given after a primary treatment, e.g. after removal of a brain tumour

• Alkylating agents

  A family of anticancer drugs that interfere with a cell’s DNA to stop it growing

• Anaplastic

  When cells divide rapidly and bear little or no resemblance to normal cells in appearance or function.

• Anterior

  The front of a structure, or a structure found toward the front of the body.

• Anti-angiogenic therapy

  Treatment which blocks the formation of new blood vessels around a tumour

• Antibody

  An antibody is a protein made by the white blood cells to combat foreign substances

• Antigens

  Any substance capable of inducing a specific immune response and of reacting with the products of that response

• Artifact

  Fuzziness or distortion in an image caused by manipulation, such as file compression

• Astrocytes

  A large, star-shaped cell that forms a supportive network for brain tumour tissue

• Asymptomatic

  If you are asymptomatic it means you don’t have any symptoms

• Avastin (Bevacizumab)

  A monoclonal antibody that interferes with the blood supply to a brain tumour. It blocks the formation of new blood vessels

• Awake craniotomy

  Neurosurgery done with the patient awake for all or part of the surgery

• Axial

  Perpendicular to the long axis of the body

• Axial (intra and extra)

  Axial is the position as it relates to the central nervous system (CNS). Intra-axial is within the CNS; extra-axial is outside the CNS

B

• Benign

  Usually slow growing, less tendency to invade and often curable if completely removed

• Biopsy

  A medical test performed by a surgeon or an interventional radiologist who will take a sample of cells or tissues for examination

• Biopsy only

  A surgical procedure to remove a small piece of tumour for examination to make a diagnosis. This is not performed as part of the surgery to remove the tumour but is a separate procedure

• Blood brain barrier (BBB)

  A barrier between brain tissue and circulating blood. It is there to protect the brain and prevents substances from leaving the blood and crossing into the brain tissues

• Brain shift

  Deformation and shift of brain tissue during neurosurgery

• Brain stem

  The bottom portion of the brain, which connects the cerebrum to the spinal chord

• Burr hole

  A hole made in the skull by a special drill with a rounded tip

C

• Calcification

  Deposits of calcium in the tissues

• Cannula

  A thin tube inserted into a vein or body cavity to administer medicine, drain off fluid, or insert a surgical instrument

• Carmustine (BCNU)

  A chemotherapy agent used to treat brain tumours

• Caudal

  Postioned underneath or toward the bottom. Sometimes referred to as inferior

• Cell

  The basic structural and functional unit in people and all living things. Each cell is a small container of chemicals and water wrapped in a membrane.

• Cellular packing density

  A large collection of non-overlapping solid objects (particles) is called a packing. They are useful models for the structures of brain tumours. The packing density is defined as the fraction of space covered by the particles. This can be used to model the growth of a brain tumour.

• Cerebellum

  The second largest structure of the brain, the cerebellum is located just above the neck in the back of the head

• Cerebrum

  The largest area of the brain, which occupies the uppermost part of the skull. It consists of two halves (hemispheres)

• cGy (centiGrays)

  A unit of absorbed radiation dose equal to one hundredth

• Chemosensitive

  The susceptibility of tumour cells to the cell-killing effects of anticancer drugs

• Chemotherapy

  Drug therapy for cancer

• Chromatin

  The protein structures that package DNA and regulate its function, in cancer stem cells

• Chromosome

  Part of a cell that contains genetic information

• Clinical presentation

  The picture of signs and symptoms, which leads to a diagnosis

• Coarse

  Thick, rough appearance. This can be used to describe the abnormal chromatin in tumour nuclei

• Concomitant

  Happening at the same time e.g. concomitant temodal with radiotherapy

• Concurrent

  Happening at the same time. Radiotherapy and chemotherapy are often referred to as concurrent when they are given at the same time.

• Conformal

  Radiotherapy beams are shaped in three dimensions to match the shape of the tumour

• Contrast

  1) The degree to which light and dark areas of an image differ in brightness or in optical density.

  2) A contrast agent is a substance injected into the body that illuminates certain structures that would otherwise be hard to see on the radiograph (film).

• Coronal plane

  The plane of the body that divides front from back.

• Corpus Callosum

  Nerve fibres that pass through and connect the two halves of cerebral hemispheres

• Cortex

  The outer layer of the brain

• Cortical mapping

  Cortical maps identify the language, motor, and sensory areas of the cortex and are often used during brain surgery

• Craniocaudal

  The direction of entry of the x-ray beam. The beam enters at the cranial end of the part being examined and exits at the caudal end

• Cranium

  The top portion of the skull

• CSF (cerebrospinal fluid)

  A watery fluid that is continuously produced and absorbed and that flows in the ventricles within the brain and around the surface of the brain and spinal cord

• CT (computerised tomography)

  X rays are aimed at slices of the body (by rotating equipment) and the results are assembled with a computer to give a three-dimensional picture of a structure

• Cyberknife®

  Brand name of a machine used to deliver linear accelerator stereotactic radiosurgery

• Cyst

  A cyst in the brain is a sphere filled with fluid, similar to a miniature balloon filled with water. Cysts may contain fluid, blood, minerals, or tissue.

• Cystic

  A cyst in the brain is a sphere filled with fluid, similar to a miniature balloon filled with water. Cysts may contain fluid, blood, minerals, or tissue. If a tumour has cystic components then it may contain some of these things.

• Cytoplasm

  The fluid inside a cell but outside the cell’s nucleus. Most chemical reactions in a cell take place in the cytoplasm.

• Cytostatic

  An agent that stops cell growth or division

D

• Debulking

  A surgical procedure to reduce the size of a brain tumour by removing a portion of it

• Delineation

  The outline of the tumour. Also used to delineate target volume of tumour for surgery and radiotherapy

• Demyelination

  Loss of the myelin sheath of a nerve

• Dexamethasone

  A corticosteroid drug used to treat inflammation

• Diffuse

  Widely spread; not confined or localised

• Dis-cohesive

  Cells that do not stick to each other

• Dose

  The total amount of ionizing radiation absorbed by material or tissues, expressed in centigrays

• Dose rate

  The quantity of a treatment given over a period of time

• DTI (diffusion tensor imaging)

  A refinement of magnetic resonance imaging (MRI) that allows the doctor to measure the flow of water and track the pathways of white matter in the brain. DTI is able to detect abnormalities in the brain that do not show up on standard MRI scans.

• Dura

  The outermost of the three meninges

E

• EEG (electroencephalogram)

  A record of the tiny electrical impulses produced by the brain’s activity. By measuring characteristic wave patterns, the EEG can help diagnose certain conditions of the brain.

• Eloquent

  Used to describe an area of the brain that is essential for basic neurological functions. Damage to these areas may result in the loss of sensory processing or linguistic ability.

• End of life

  A phrase used to describe a phase of illness which has become advanced, progressive and incurable

• Endocrine system

  The tissues or glands in the body that secrete hormones

• Endothelial

  The main type of cell found in the inside lining of blood vessels in the brain

• Enhancement

  A substance is used to enhance the structures within the brain during a scan. This reduces the lowest grey values to black and the highest to white.

• Eosinophilic

  Staining a cell or tissue with the pink dye eosin. This is characteristic of many of the low grade glial tumours.

• Ependymal

  A cell that forms the lining of the fluid-filled spaces in the brain and spinal cord. It is a type of glial cell.

• Excision

  A cut

• External Beam

  Radiation therapy that uses a machine to aim x rays at a brain tumour

F

• Fibrillary

  Made up of minute fibres

• First line management

  Initial treatment of an illness

• FLAIR (Fluid attenuated inversion recovery)

  A pulse sequence used in scanning to null signal from fluids. For example, it can be used in brain imaging to suppress cerebrospinal fluid (CSF).

• fMRI (functional MRI)

  Functional MRI takes the map obtained with traditional MRI imaging, and adds on additional dimensions, such as measuring regional blood flow over time, or something about the biochemistry of tissue of a brain tumour in a specified location in the brain

• Focal

  Limited to a specific area

• Foci

  Foci is the plural of focus.It suggests microscopic visualisation of the tumor cells. Under a microscope therefore you might see more than one indication of one or two microscopic foci of possible invasion.

• Fractionated

  Dividing the total dose of radiation to be given into several smaller, equal portions delivered over a period of days

G

• Gadolinium

  A substance that enhances tumour images using magnetic resonance imaging (MRI).

• Gamma Knife ®

  Brand name of a machine used to deliver stereotactic radiosurgery (SRS), a focal form of radiation therapy

• GFAP

  Short for Glial Fabrillary Acidic Protein. This is a gene. It provides instructions for making GFAP protein, a member of the family that provides support and strength to cells.

• Gliadel ®

  The brand name of a wafer used to deliver chemotherapy

• Glial cells

  Any of the cells that hold nerve cells in place and help them work the way they should. The types of glial cells include oligodendrocytes, astrocytes, microglia, and ependymal cells. Also called neuroglia.

• Gliolan/5 ALA ®

  Gliolan is a powder to be made up into a solution to be taken by mouth. Gliolan is used in adult patients with malignant glioma. It helps surgeons to see the tumour more clearly during an operation to remove it from the brain

• Global

  Throughout the brain

• Grade

  A brain tumour will be given a grade which refers to the way the cells of the tumour look under a microscope. Grade 1 (low grade) refers to tumours that appear less likely to spread and grade IV (high grade) refer to tumours that appear to grow more quickly, or are most malignant. The brain tumour will be graded according to the highest grade of cell that the pathologist sees in the biopsy specimen. So if the tumour has a high percentage of grade II cells, and a small percentage of grade III cells, the tumour will be graded as a grade III.

• Gross total resection

  Removal of all the tumour

H

• Halo

  An area of perinuclear clearing

• Heterogeneity

  A state of having different characteristics and qualities

• Heterogeneous

  A state of having different characteristics and qualities

• High grade

  Tumours that appear to grow more quickly, or are most malignant

• Histology

  The study of tumour cells under a microscope

• Histopathology

  The study of diseased tissues at a minute (microscopic) level

• Homogeneous

  Of a uniform, consistent nature

• Hydrocephalus

  An abnormal buildup of cerebrospinal fluid (CSF) in the ventricles of the brain

• Hyperchromatic

  Abnormally highly coloured or excessively stained

• Hyperostosis

  An excessive growth of bone

• Hypothalamus

  The region of the brain that forms part of the wall of the third ventricle. It is part of the endocrine system.

I

• IDH-1

  Short for Isocitrate Dehydrogenase. IDH is an enzyme, one form of which participates in the citric acid cycle

• Image guidance

  A surgical procedure where the surgeon uses tracked surgical instruments to indirectly guide the procedure

• Imaging

  The use of technology to create a picture of the brain e.g. MRI scan

• Immunocytochemistry

  Technique which uses specific antibodies to identify and stain tissue

• Immunohistochemistry (IHC)

  The process of detecting antigens or biological markers within tumours or brain tissue using antibodies. Immunohistochemistry provides insight about the classification of brain tumours by identifying cellular markers of phenotype and about the tumour’s potential to grow.

• Immunoreactive

  Reacts with an antibody

• iMRI

   A form of MRI called intraoperative magnetic resonance imaging. It is used to see brain tumours clearly while performing surgery.

• IMRT (intensity modulated radiation therapy)

  Specialised equipment that shapes radiation beams to the size and shape of the tumour

• Increased (high) signal

  Hyperintensity signals show up as increased brightness (white) on MRI using different scanning techniques. The nature of brain scans causes tissues with more water to give off brighter signals that appear whiter on the scans.

• Inflammation

  Swollen brain tissue

• Infra-tentorial

  Below the tentorium

• Intracranial

  Inside the cranium

• Intracranial haemorrhage

  Bleeding within the skull

• Intracranial pressure (ICP)

  Pressure inside the cranium

• Intravenous

  Into the vein

• Intrinsic

  Originating from, or situated within, an organ or tissue

• Isotope

  A form of a chemical element that has a different-from-normal atomic mass. Isotopes are used in a number of medical tests because they can produce images of tissues that can be used to detect diseases or conditions.

K

• Ki67

  An antigen that detects cells in synthesis phase (the period when the chromosomes are replicated).

L

• Late effects

  A health problem that occurs months or years after a disease is diagnosed or after treatment has ended

• Laterality

  The side of the body in which symptoms are showing

• Lesion

  A brain lesion describes damage or destruction to any part of the brain. It may be due to trauma or any other disease that can cause inflammation, malfunction, or destruction of a brain cells or brain tissue

• Leukopenia

  A reduction in the number of white cells in the blood

• LINAC (linear accelerator)

  An electrical device that creates ionising radiation in the form of x-rays (photons)

• Lobe

  One of four sections of the cerebral hemispheres

• Localised

  Confined or restricted to an area

• Lomustine (CCNU)

  A chemotherapy agent used to treat brain tumours

• Low grade

  Tumours that appear less likely to spread

M

• Macroscopy

  Examination with the naked eye

• Malignant

  Cancerous, tending to invade normal tissue or to recur after removal

• Margin

  A border or edge of the tumour

• Markers

  Pathologists can test for markers in the tumour tissue. Markers can be genetic, molecular or immunohistochemistry. These tests can:

• Mask

  A mould to keep your head from moving so that you are in the exact same position for each treatment

• MDT

  Multidisciplinary team meeting

• Median survival

  Average survival time for patients with a certain tumour. 50% will survive longer than the median survival and 50% will survive less.

• Meninges

  A membrane (one of 3) that envelops the brain and spinal cord)

• Metabolism

  The chemical and physical processes that happen to maintain the body and produce energy

• Metastasis/metastases

  Spread to another part of the body, usually through blood vessels, lymph channels or spinal fluid.

• Metastatic brain tumour

  A secondary brain tumour formed of cancer cells that began elsewhere in the body e.g. lung, breast, colon, kidney, skin

• MGMT

  Abbreviation for 06-methylguanine –DNA methyltransferase, a gene thought to play a role in DNA repair

• MIB1

  A gene that regulates cell death (apoptosis)

• Micro-calcification

  A tiny abnormal deposit of calcium salts

• Microvascular proliferation

  Abnormally thickened blood vessels which tend to be seen in higher grade gliomas. They tend to be leaky and cause contrast enhancement on imaging

• Midline

  An imaginary line running along the surface of the brain (front to back), which separates the right and left hemispheres

• Mitoses

  The number of cells dividing

• Modality

  A method of treatment

• Molecular analysis

  The analysis of human DNA, RNA, and chromosomes to establish a diagnosis or prognosis

• Monoclonal

  Deriving from a single cell

• Morphology

  The form and structure e.g. of a tumour

• Motor

  Movement, control of muscles

• MRI (magnetic resonance imaging)

  A special radiology technique which takes pictures of internal structures of the body using magnetism, radio waves, and a computer to produce the images of body structures

• Multifocal

  Having many focal points. Damage caused by the disease occurs at multiple sites

• Multinucleated

  Having more than one nucleus per cell

• Myelin sheath

  The insulating envelope of myelin that surrounds the core of a nerve fibre. It facilitates the transmission of nerve impulses.

• Myelosuppression

  A decline or absence of blood cell production

N

• Necrosis

  Dead cells in tissue

• Neoplasm

  A tumour, either benign or malignant

• Neoplastic

  Used to describe abnormal new growth of tissue

• Neuro-oncology

  The branch of medical science dealing with tumours of the nervous system

• Neuroendoscope

  An endoscope for examining and performing various interventions in the central nervous system

• Neuroendoscopy

  The use of a neuroendoscope with the aid of a neuronavigation system to examine the central nervous system and perform minimally invasive neurosurgical procedures.

• Neurofibrillary matrix

  Extracellular background in which the cell sits

• Neuronavigation

  Pre-operative MRI information, fed into a computer, that allows the surgeon to view 3D images during surgery

• Neuropathology

  The study of diseases of the nervous system, which includes the brain

• Neurotoxicity

  Damage to the nervous system

• Neutropenia

  An abnormal decrease in the number of neutrophils, a type of white blood cells

• Nitrosureas

  A group of anticancer drugs able to cross the blood brain barrier

• Nuclear

  Forming a nucleus

• Nucleus

  The structure in a cell that contains the chromosomes

O

• Occipital lobe

  The lobe of the cerebral hemispheres at the back of the head, just above the neck

• Oedema

  Swelling caused by fluid

• Oligodendrocytes

  Cells that cover and protect nerve cells in the brain and spinal cord

• Oligodendroglial

  Describes a slow-growing tumor that begins in oligodendrocytes.

• Optimal

  Most desirable or satisfactory

• Oral

  By mouth

• Overall survival (OS)

  The percentage of people in a study or treatment group who are still alive for a certain period of time after they were diagnosed with or started treatment for a disease

P

• Palisading

  The lining up of cells which gives them the ordered appearance of a fence

• Palliative

  Therapy with the goal of relieving symptoms and improving quality of life

• Palliative radiation

  Radiation therapy with a goal of relieving symptoms and improving quality of life

• Paraffin

  Used in tissue preparation and processing

• Parietal lobe

  The lobe of the cerebral hemispheres at the upper back area of the head.

• Partial

  Not total. Some tumour could not be removed

• Pathology

  The branch of medicine that looks at abnormal changes in cells and tissues which signal disease

• PCV regimen (procarbazine, lomustine (CCNU), vincristine)

  A combination chemotherapy regimen

• Perfusion MR

  A special type of MRI that uses an injected dye in order to see blood flow through tissues

• Perinuclear

  Situated around a nucleus

• PET (position emission topography)

  A scanning device which uses low dose radioactive sugar to measure brain activity

• Pleomorphic

  Varying in cell shape

• Posterior

  The back of a structure, or a structure found toward the back of the body.

• Prognosis

  A forecast as to likely outcome, the chance of recovery

• Progression free survival (PFS)

  The length of time during and after the treatment of a disease that a patient lives with the disease but it does not get worse.

• Proliferation

  The growth and reproduction of similar cells.

• Prophylaxis

  Preventative

• Proton beam

  A treatment that uses high energy beams to treat tumours

• Pseudoprogression

  Swelling or contrast enhancement on a scan which suggests tumour progression or recurrence, when it is treatment effect. Pseudoprogression can stabilise without additional treatments and often remains clinically asymptomatic

R

• R132H

  The most common point mutation of IDH1.This mutation is more commonly seen in lower grade gliomas and the higher grade gliomas that derive from them

• Radiation oncology

  The use of radioactive substances and x-rays for the treatment of brain tumours

• Radiosurgery

  A special form of radiation therapy that uses a large number of narrow, precisely aimed, high dose beams of ionising radiation

• Radiotherapy

  A treatment in which high-energy rays are used to damage cancer cells and stop them from growing and dividing

• Regime

  A regulated system of treatment

• Resection

  Surgical removal of a brain tumour

S

• Saggital plane

  The plane of the body that divides right from left.

• Segmental

  Made up of segments

• Shunt

  A drainage system inserted in the brain to drain fluid from a ventricle into a body cavity

• Signal

  Brightness of a tissue or structure on MRI

• Single agents

  Treatment with a single chemotherapy agent; i.e., treatment with one type of chemotherapy drug, rather than with a combination of different chemotherapy drugs

• Sonowand ®

  Technology which enables the surgeon to update the map during surgery, scanning the brain with real time 3D ultrasound.

• Specimen

  A sample of tissue, blood, or urine which is used for analysis and diagnosis

• SPECT (single photon emission computed tomography)

  A scanning technique which uses radioactive materials

• Stereotactic

  Precise positioning in a 3D space

• Stereotactic biopsy

  A biopsy accomplished with a computer guided needle

• Stereotactic radiosurgery (SRS)

  A form of radiation therapy that focuses high-powered x-rays on a small area of the body, better targeting the abnormal area. It is a treatment, not a surgical procedure. Some types of stereotactic radiosurgery require a specially fitted face mask or a frame attached to your scalp

• Steroid

  Medication used to reduce swelling and inflammation around a brain tumour

• Sub-total resection

  Less than total surgical removal of a tumour

• Subcortical

  The region of the brain below the cortex

• Supra-tentorial

  Above the tentorium

• Suture

  A stitch

• Systemic

  Affecting or circulating throughout the body

T

• T1 weighting

  MRI image showing structures; cerebrospinal fluid appears black on the image

• T2 weighting

  MRI image showing water; oedema and cerebrospinal fluid appear white on the image

• Temozolomide (TMZ)

  An anti cancer drug that belongs to the family of drugs called alkylating agents

• Temporal lobe

  The lobe of the cerebral hemispheres that sits behind the ears.

• Tentorium

  A flap of the meninges separating the cerebral hemispheres from the brain structures

• Thalamus

  The area surrounding the third ventricle. Its primary function is to relay sensory information.

• Thrombocytopenia

  A decrease in the normal number of platelets in the blood

• Tissue

  A group or layer of cells that work together to perform a specific function

• Toxicity

  State of being poisonous

• Trajectory

  A chosen course

• Tumour progression

  When a tumour recurs, or begins to grow again. The second stage of tumour development

V

• Vascular

  Relating to the blood vessels of the body

• Vascularity

  The blood supply of a tumour

• Ventricles

  Four connected cavities in the brain through which cerebrospinal fluid flows

W

• WBRT (whole brain radiotherapy)

  A type of external beam radiotherapy which is given to the whole brain over a period of weeks.

• WHO classification

  The World Health Organisation (WHO) classification for the grading of brain tumours

  – aid the diagnosis of brain tumours which are sometimes hard to diagnose
  – allow clinicians to work out a prognosis
  – indicate whether a tumour will respond to a specific type of treatment.