· CA Cancer.
· calcification [kal sih fih kay´ shun] Deposit of calcium. Associated with some types of brain tumors, as meningiomas, oligodendrogliomas and astrocytomas.
· CALGB Cancer & Acute Leukemia Group B, an NCI funded clinical cooperative group organized to test new treatments for adult cancer patients.
· cancer [kan´ sur] Malignant tissue. It can invade and destroy healthy tissue, and tends to spread to distant locations. Cancer cells are abnormal and divide without control.
· Cancer Information Service 1-800-422-6237; TTY 1-800-332-8615. A national information service (in English or Spanish) of the National Cancer Institute for patients, the public and health professionals. Abbreviated CIS.
· cancer of unknown primary origin Cancer cells are found but the place where they first arose (the original or primary site) cannot be located.
· Cancer Trials Support Unit A pilot project sponsored by the National Cancer Institute. It is charged with simplifying administrative procedures performed by Clinical Cooperative Groups. Abbreviated CTSU.
· CANCERLIT Cancer Literature. A bibliographic database that contains references to cancer literature published in over 4,000 different sources including biomedical journals, proceedings, books, reports and doctoral theses from 1963
to the present. Most records contain abstracts and all contain citation information, descriptive fields such as document type and the language in which the document was written.
· cancer.gov The National Cancer Institute’s cancer information website, it provides access to a wide variety of information, including clinical trials from PDQ, cancer literature from CANCERLIT and a wealth of other information. The complete web site address is www.cancer.gov.
· carcinogen [kar sin´ o jen] Any substance known to cause cancer. The amount of time from exposure to symptoms and diagnosis may be years or even decades.
· carcinogenesis [kar sin o jen´ eh sis] The process by which normal cells are transformed into cancer cells.
· carcinoma [kar sih no´ ma] A malignant tumor that arises from skin or the lining of internal body organs, for example,
the breast, prostate, lung, stomach or bowel. Carcinomas often invade adjacent tissue and spread to distant organs, including the brain.
· CARRA Consumer Advocates in Research and Related Activities, a program of the National Cancer Institute (NCI) that matches cancer advocates to a variety of NCI activities
· CAT Computerized Axial Tomography. Also called CT, Computerized tomography.
· catheter [kath´ ih tur] A thin, flexible, tube. Used to insert, remove or relocate fluids in the body.
· cauterize [kaw´ tur eyes] To treat tissue with a hot instrument, an electric current or a caustic substance. Used during surgery to control bleeding.
· Cavitron Brand name of an ultrasonic aspirator — sometimes used to break tumors apart and suction out the pieces during surgical removal of a tumor.
· CBA Cost Benefit Analysis.
· CBC Complete Blood Count.
· CBER Center for Biologicals Evaluation and Research of the Food and Drug Administration. This office is responsible for ensuring the safety, effectiveness and timely delivery to patients of biological products, including blood and blood products, vaccines, human tissue for transplantation, allergenic materials and anti-toxins, and biological therapeutics. Biologics, in contrast to drugs that are chemically synthesized, are derived from living sources (humans, animals, and microorganisms.)
· CBTC Canadian Brain Tumor Consortium.
· CBTNet Canadian Brain Tumor Network.
· CBTRUS Central Brain Tumor Registry of the United States. A private, not-for-profit agency committed to providing a resource for gathering and disseminating current data on all primary brain tumors, malignant and benign, for the purposes of accurately describing their incidence and survival patterns, evaluating diagnosis and treatment, facilitating etiologic studies, establishing awareness of the disease, and ultimately, for the prevention of all brain tumors.
· CC Chief Complaint.
· CCC — SLP Certificate of Clinical Competence — Speech-Language Pathologist. A speech-language pathologist is a healthcare professional educated and trained to evaluate and treat people with speech, language and swallowing problems.
· CCG Children’s Cancer Study Group. An NCI funded clinical cooperative group organized to evaluate new treatments for pediatric patients. CCG, the Pediatric Oncology Group (POG) and two other pediatric clinical cooperative groups have merged to form a new group — the Children’s Oncology Group (COG).
· CCN Certified Clinical Nutritionist.
· CCOP Community Clinical Oncology Program, a National Cancer Institute effort that allows community physicians to work with scientists conducting NCI-supported clinical trials.
· CCRA Certified Clinical Research Associate.
· CCRN Critical Care Registered Nurse.
· CDC Centers for Disease Control and Prevention, Department of Health and Human Services; located in Atlanta, Georgia.
· CDER Center for Drug Evaluation and Research of the
Food and Drug Administration. This office is responsible for
ensuring the safety and effectiveness of drugs. An Office of Oncology Drug Products (ODP) in CDER’s Office of New Drugs is responsible for the review of drugs and biologic products used to diagnose, treat, and
· cell The basic living unit of body tissue. It contains a nucleus surrounded by cytoplasm and is enclosed by a membrane.
· CDRH Center for Devices and Radiological Health of the Food and Drug Administration. This office helps ensure that medical devices are safe and effective and helps reduce
unnecessary exposure to radiation from medical, occupational, and consumer products. Radiation emitting products include microwave ovens, televisions, medical x-ray machines, CT/MRI scans, and diagnostic ultrasound among others.
· CEA carcinoembryonic antigen. This is a marker for a tumor of the arachnoid and/or pia mater membranes of the meninges.
· CED Convection-Enhanced Delivery.
· Cediranib - A drug being investigated for its potential as an angiogenesis inhibitor.
· cell adhesion Refers to the bonding together of cells, their “stickiness.”
· cell cycle The reproductive stages of a cell leading to cell division (mitosis).
· cell differentiation The process that young, immature, unspecialized (undifferentiated) cells undergo as they take on individual characteristics and reach their mature, specialized (differentiated) form and function.
· cell kinetics [ki net´ ix] The amount of time it takes for a tumor to attain a determined size.
· cell motility The ability of a cell to move.
· cell proliferation An increase in the number of cells as a result of cell division.
· cellular ependymoma [ep en dih mow´ ma] A low grade tumor most commonly located in the fourth ventricle and the midline.
· cellular immunity Immune protection provided by the direct action of immune cells as distinct from the action of antibodies (humoral immunity).
· center of excellence There is no agreed-upon definition of this term.
· centigray One one-hundredth of a gray, the unit of measure in radiation therapy. Abbreviated cGy.
· central nervous system Pertaining to the brain, cranial nerves and spinal cord. It does not include muscles or peripheral nerves. Abbreviated CNS.
· central neurocytoma [nur o sigh toe´ ma] This rare, low grade tumor typically occurs in a lateral ventricle in the region of the foramen of Monro, and occasionally extends into the third ventricle as well.
· cerebellar astrocytoma [sair uh bell´ ur • as tro sigh toe´ ma] A glial tumor of the cerebellum. About 80% are low grade, localized, cystic tumors although higher grades of tumor also occur. More common in children than adults.
· cerebellar glioma [sair uh bell´ ur • glee o´ ma] The generic name given to a glial tumor of the cerebellum.
· cerebellar peduncle [sair uh bell´ ur • pea dung´ kul] The nerve fibers connecting the cerebellum and the brain stem.
· cerebellopontine angle [sair uh bell´ o pon´ teen] The angle between the cerebellum and the pons, a common site for the growth of vestibular schwannomas, which are also called acoustic neuromas.
· cerebellum [sair uh bell´ um] Located just above the neck in the back of the head, the cerebellum is the second largest structure in the brain. It consists of two hemispheres or halves, is connected to the brain stem, and controls balance for walking and standing and other complex motor functions.
· cerebral aqueduct [ser e´ brul • ok´ weh dukt] A narrow canal through the midbrain connecting the third and fourth ventricles through which cerebrospinal fluid flows. Also called the aqueduct of Sylvius.
· cerebral neuroblastoma [ser e´ brul • nur o blas toe´ ma] The cerebral neuroblastoma is a malignant, rapid growing tumor. Eighty-five percent of cerebral neuroblastomas occur in children. It is also called a PNET (primitive neuroectodermal tumor) by some. Neuroblastoma more commonly occurs outside the central nervous system.
· cerebrospinal fluid [ser ee´ bro spy´ nal] The clear fluid made in the ventricular cavities of the brain that bathes the brain and spinal cord. It circulates through the ventricles and the subarachnoid space. Abbreviated CSF.
· cerebrum [ser e´ brum] The largest area of the brain, the cerebrum occupies the uppermost part of the skull. It consists of two halves called hemispheres. Each half of the cerebrum is further divided into four lobes: frontal, temporal, parietal and occipital. The right side of the cerebrum generally controls the left side of the body. Also called cerebral hemispheres.
· cervical Refers to the neck.
· cervicomedullary brain stem glioma [ser´ vih koh med´ you lair ee] This tumor arises in the medulla oblongata and extends into the cervical spinal cord. It is often a pilocytic or fibrillary astrocytoma.
· cervicomedullary junction [ser´ vih koh med´ you lair ee] Where the extension of the spinal cord becomes the medulla oblongata of the brain.
· cGy Centigray.
· CHAMPUS Civilian Health and Medical Program of the Uniformed Services (United States), a federally funded health program that provides Uniformed Services beneficiaries with medical care supplemental to that available in military and Public Health Service facilities. All CHAMPUS beneficiaries move over to Medicare at age 65. CHAMPUS is like Medicare in that the government contracts with private parties to administer the program.
· chemoresistance [KEE-MO resistance] Cellular resistance to a drug or group of drugs.
· chemoresponsive [KEE-MO responsive] Cellular sensitivity to a drug or group of drugs.
· chemotherapy [key mo ther´ ah pee] The use of anti-cancer chemicals (drugs) to treat brain tumors.
· CHIP Comprehensive Health Insurance Program, regulated by individual states.
· choked disc Swelling of the optic nerve indicating increased intracranial pressure. Also called papilledema.
· chondroma [kon drow´ ma] A rare, benign tumor that tends to arise at the base of the skull.
· chondrosarcoma [kon drow´ sar ko´ ma] A rare tumor, it is the malignant form of the chondroma and is most common in adult males.
· chordoma [kor doe´ ma] A rare, slow-growing, but often intractable, extradural tumor occurring at the base of the skull, or at the end of the spine.
· choriocarcinoma See germ cell tumor.
· choroid plexus [ko´ royd • pleks´ sus] Areas in the ventricles where cerebrospinal fluid is formed.
· choroid plexus carcinoma [ko´ royd • pleks´ sus • kar sih no´ ma] Occurring primarily in children, this is the malignant form of the choroid plexus papilloma. It comprises about ten percent of all choroid plexus tumors and typically occurs in one of the lateral ventricles. Also called anaplastic choroid plexus papilloma.
· choroid plexus papilloma [ko´ royd • pleks´ sus • pap ih low´ ma] A rare, benign tumor most common in children under the age
of two. The lateral ventricles are the most common location
in young children, the fourth ventricle is the most common
site in adults.
· chromosome [crow´ moe soam] Structures in the nucleus of a cell that carry genes. All human cells contain 46 chromosomes (23 pair). Chromosomes are composed of DNA.
· chromosome deletion A portion of a chromosome is missing at least one gene.
· chronic A disease or condition that persists over a long period of time. Not acute.
· Cilengitide – A drug being investigated for its potential as an angiogenesis inhibitor.
· cingulate cortex [sin´ gyou lat • kor´ teks] A bundle of nerve fibers in the white matter located over the surface of the corpus callosum.
· circumscribed [sir´ come skribd] Having a border, localized. Often associated with a capsule and benign tumors of the brain, for example, meningiomas, pituitary adenomas and acoustic neuromas.
· CIS Cancer Information Service. A service of the National Cancer Institute, it is a national information network for patients, the public and health professionals. Cancer Information Service provides the latest cancer information through a toll-free telephone service, and can respond in English or Spanish. Access by phone: 1-800-422-6237; TTY 1-800-332-8615.
· classification A system for grouping tumors based on shared characteristics. Brain tumors are classified by their microscopic anatomy on the assumption that each kind of tumor results from the abnormal growth of a specific cell type. Classification is thought to help predict a tumor’s behavior, the patient’s prognosis and to serve as a guide to treatment.
· clear cell ependymoma [ep en dih moe´ ma] A low grade tumor most commonly located in the fourth ventricle and the midline.
· clinical That which can be observed in or involves patients. Research treatments tested on patients, as opposed to laboratory or animal testing.
· clinical cooperative group A network of physicians from various medical institutions investigating new treatments by planning and implementing research studies. Because of the relative rarity of brain tumors, most doctors and hospitals could not enter sufficient numbers of patients into a protocol (clinical trial) to derive meaningful data or it would take a very long time to do so. Clinical cooperative groups and consortia were created by the National Cancer Institute so that new treatments could be evaluated quickly.
· clinical investigator A physician who administers treatments being studied in clinical trials.
· Clinical Nurse Specialist A registered nurse with a master’s degree in nursing who has demonstrated a high degree of knowledge, skill and competence in a specialized area of
· clinical trial An organized process for testing new treatments on patients using a pre-defined treatment plan called a protocol. Clinical trials might be sponsored by the National Cancer Institute, another of the institutes of the National Institutes of Health, pharmaceutical companies, or individual treatment centers.
· ClinicalTrials.gov The US National Institutes of Health web site listing of federally and privately supported clinical trials. The complete web site address is www.clinicaltrials.gov.
· clivus [kli´ vus] An area at the base of the skull composed of part of the sphenoid and occipital bones.
· clone [klone] A group of genetically identical cells or organisms descended from a single common ancestor; to reproduce multiple identical copies.
· CMS Centers for Medicare & Medicaid Services. The federal agency within the US Department of Health and Human Services responsible for Medicare, Medicaid, State Children’s Health Insurance Program (SCHIP), Health Insurance Portability and Accountability Act (HIPAA), and Clinical Laboratory Improvement Amendments (CLIA).
· CNP Certified Nurse Practitioner.
· CNRN Certified Neuroscience Registered Nurse.
· CNS Central Nervous System. The brain, spinal cord and
· CNS Congress of Neurological Surgeons, a professional society.
· CNS metastasis [meh tas´ tah sis] Cancer that has spread from its original (primary) site to the brain or spinal cord.
· CNS prophylaxis [pro fi lak´ sis] Treatment to prevent a cancer from spreading or growing in the brain or spinal cord even if it hasn’t yet been detected.
· CNS tumor A tumor of the brain, its covering, or the spinal cord.
· cobalt machine [ko´ bawlt] Uses cobalt isotopes as the radiation source. A nuclear reactor manufactures the isotopes.
· COBRA Consolidated Omnibus Budget Reconciliation Act of 1986. This act provides employees or covered dependents the right to continue their group healthcare coverage for a defined period of time if the employee is fired or experiences another qualifying event.
· COG Children’s Oncology Group. A clinical cooperative group funded by the National Cancer Institute to test new treatments in children with cancer. It was formed as a
consolidation of the CCG (Children’s Cancer Group), POG (Pediatric Oncology Group) and two other pediatric cancer groups.
· co-deletion [KOH-deleshun] A deletion is a type of mutation involving the loss of genetic material. It can be small, involving a single missing DNA base pair, or large, involving a piece of a chromosome. A co-deletion is a deletion of two chromosomes that occurs simultaneously, such as the 1p19q co-deletion often found in oligodendrogliomas.
· cognition [cog nih´ shun] The mental process involving thinking, learning, understanding, and memory.
· colloid cyst [kol´ oyd • sist] A cyst is a tumor-like sphere filled with fluid, similar to a balloon filled with water. Colloid cysts are most frequently located in the third ventricle and almost always occur in adults.
· colony-stimulating factor A substance that stimulates the production of blood cells. G-CSF is the abbreviation for granulocyte colony-stimulating factor; GM-CSF is the abbreviation for granulocyte-macrophage colony-stimulating factor.
· combination chemotherapy Drugs given in combination to increase their individual effectiveness.
· community standard of care The generally accepted prudent and appropriate practice of healthcare in a given locale.
· Compass System A frameless stereotactic system that combines a microscope, laser and computer.
· complementary medicine Therapies used in addition to conventional treatment primarily to manage or prevent pain, nausea and treatment related side-effects; to reduce stress and anxiety; to promote healing. Also called holistic or natural medicine.
· complete remission The most common definition is that the tumor can no longer be seen on scans as a result of treatment. Remissions can be permanent or temporary. Also called complete response. Abbreviated CR.
· complex partial seizure One of two types of focal seizure. It affects only one part of a cerebral hemisphere and symptoms depend on the specific part involved. The other type of focal seizure is called a simple partial seizure.
· concave [kon kave´] Having a hollowed, inward surface, like the following: (insert concave symbol) .
· conformal Shaped to follow the irregular borders of a tumor.
· conformal radiation For therapy, the radiation beams are shaped in three dimensions to match the shape of the tumor. The shaping is accomplished by special equipment and special computer programs. Abbreviated CRT. Also called 3D-CRT.
· congenital [kon jen´ ih tul] Existing before or at birth.
· consortium An NCI-funded network of hospital and physicians established to evaluate new treatments in Phase I and Phase II clinical trials. The two brain tumor specific consortia are: ABTC (Adult Brain Tumor Consortium) and PBTC (Pediatric Brain Tumor Consortium)..
· contralateral [kon trah lat´ ur al] Affecting the opposite side.
· contrast enhancing portion “Contrast” materials are the dyes used to make parts of the brain more obvious than others on scan. Contrast dyes create a difference of signal intensities, resulting in some tissues being displayed differently on the scan images. The portion of the tumor absorbing the dye, called the “contrast-enhancing portion” of a tumor, may be more dense than surrounding tissue, and will therefore stand out more in an MRI. Contrast enhancement is linked to breakdown of the blood-brain barrier and angiogenesis.
· control group Patients receiving standard treatment. In clinical trials, the control group is compared to the group that received an investigational treatment.
· convection-enhanced delivery A new technique used to deliver a drug directly into the area of a tumor using the principles of constant pressure to “flow” substances. Following placement of catheters by a neurosurgeon to the desired area of the brain, a drug is delivered continuously through the catheters for the number of days specified by the study design. Abbreviated CED.
· conventional fractionation A schedule for delivering radiation therapy. For primary brain tumors, the dose is prescribed usually as one fraction per day of 180 to 200 cGy, five times a week, for six weeks, for a total dose of 5400 to 6000 cGy.
· conventional medicine The mainstream medical care practiced at most hospitals in the United States. Standards of care are set by government and regulatory agencies, and by individual health insurance companies.
· conventional radiation therapy External beams of energy aimed at the tumor and delivered in daily fractions over a long period of time.
· convex [kon veks´] Having a rounded, outward surface, like the following: .
· convexity [kon veks´ ih tee] The rounded, protruding
surfaces of the brain.
· convulsion A sudden attack that causes a wide range of unusual movements, behaviors and sensations; caused by abnormal electrical activity in the cerebral hemispheres of the brain. Also called seizure.
· cooperative group A group of physicians and/or medical institutions cooperating to investigate new treatments. Because of the relative rarity of brain tumors, most hospitals or medical centers could not enter sufficient numbers of patients into a protocol (clinical trial) to derive meaningful data or it would take a very long time to do so. Cooperative groups and consortia were created by the National Cancer Institute so that new treatments could be evaluated quickly. Also called clinical cooperative group.
· coronal [kor o´ nul] Circular. In scans, an image of the top of a thin layer of the brain showing both the right and left sides.
· corpus callosum [kor´ pous • ka los´ sum] A band-like structure deep in the brain that contains fibers which connect the two halves of the cerebral hemispheres.
· cortical Refers to the cerebral cortex which is also called the cerebral hemisphere.
· corticosteroids [kor tih ko stair´ oidz] Medications used to decrease swelling and inflammation around tumors. Also called glucocorticosteroids, or more commonly, steroids.
· CR Complete Response. As a result of treatment, the tumor can no longer be seen on scans. Also called complete remission.
· CRA Clinical Research Associate.
· cranial cavity [kray´ nee ul • kah´ vih tee] The skull.
· cranial nerves [kray´ nee ul] Twelve pair of nerves, numbered from one to twelve. A part of the Central Nervous System.
· 1st cranial nerve Olfactory nerve, cranial nerve I. A pair of nerves for the sense of smell. Nerve endings in the nose send odor information to the brain.
· 2nd cranial nerve Optic nerve, cranial nerve II. A pair of nerves for the sense of sight. Nerve endings in the retina of the eyes send visual information to the brain.
· 3rd cranial nerve Oculomotor nerve, cranial nerve III. A pair of nerves that controls the muscles that control pupil
size and move the eyes up, down, up sideways and the upper
eyelid. Originates in the midbrain.
· 4th cranial nerve Trochlear nerve, cranial nerve IV. A pair of nerves that controls the muscles that move the eyes down and sideways. Originates in the midbrain.
· 5th cranial nerve Trigeminal nerve, cranial nerve V. A pair
of nerves with three divisions: the ophthalmic division carries sensory information from the scalp, membranes of the nose, and parts of the eye to the brain; the maxillary division carries sensory information from the roof of the mouth, upper lip, jaw and teeth to the brain; the mandibular division carries sensory information and controls the muscles of chewing and a muscle of the middle ear. Originates in the pons.
· 6th cranial nerve Abducens nerve, cranial nerve IV. A pair of nerves that controls the muscles that move the eye sideways. Originates in the pons.
· 7th cranial nerve Facial nerve, cranial nerve VII. A pair of nerves with two divisions: one division carries taste information from the front 2/3 of the tongue; the other
division controls muscles of the face, scalp and middle ear and the secretion of saliva and tears. Originates in the pons.
· 8th cranial nerve Acoustic nerve, Vestibulocochlear nerve, cranial nerve VIII. A pair of nerves with two divisions: the vestibular division carries information about balance and
position to the brain; the cochlear division carries information about hearing to the brain. Originates in the pons.
· 9th cranial nerve Glossopharyngeal nerve, cranial nerve IX.
A pair of nerves that carries taste information from the rear 1/3 of the tongue to the brain, controls the muscles of swallowing in the throat and the secretion of saliva from the parotid gland. Originates in the medulla oblongata.
· 10th cranial nerve Vagus nerve, cranial nerve X. A pair of nerves that carries sensory information from the throat and windpipe to the brain, and controls the muscles of the throat, windpipe, heart, lungs, stomach, bowels and part of the ear. Originates in the medulla oblongata.
· 11th cranial nerve Accessory nerve, cranial nerve XI. A pair of nerves that controls the large muscles of the neck. Originates in the medulla oblongata.
· 12th cranial nerve Hypoglossal nerve, cranial nerve XII. A pair of nerves that controls the muscles of the tongue. Originates in the medulla oblongata.
· craniectomy [kray nee ek´ toe me] Surgery performed on the skull during which pieces of bone are removed to gain access to the brain, and the bone pieces are not replaced at the end of the operation.
· craniopharyngioma [kray´ nee o fah rin jee o´ ma] A benign tumor arising from small nests of cells located near the pituitary stalk. About sixty percent of craniopharyngiomas occur in patients older than sixteen. There are two types: adamantinomatous and squamous-papillary.
· craniotomy [kray ne ot´ o me] Surgery performed on the skull during which pieces of bone are removed to gain access to the brain, and the bone is replaced at the end of the operation.
· cranium The top portion of the skull. It encloses the brain and is composed of the ethmoid, frontal, sphenoid, temporal, parietal and occipital bones.
· cribriform plate [krib´ ri form] The flat, perforated part of the ethmoid bone.
· CRT chemoradiation. Combined modality therapy with radiation and chemotherapy.
· CRT Conformal Radiation Therapy. Radiation beams are shaped to match the tumor. The shaping is accomplished by special equipment and special computer programs. Also called 3D-CRT.
· CSF Cerebrospinal fluid.
· CSF Colony-Stimulating Factor.
· CT or CAT scan Computed Tomography or Computed Axial Tomography. An x-ray device linked to a computer that produces an image of a predetermined cross-section of the brain. A special dye material might be injected into the patient’s vein prior to the scan to help make any abnormal tissue more evident.
· CTC Common Toxicity Criteria.
· CTEP Cancer Therapy Evaluation Program, Division of Cancer Treatment & Diagnosis, National Cancer Institute. CTEP administers the Clinical Cooperative Groups funded
by the National Cancer Institute.
· CTSU Cancer Trials Support Unit, a pilot project sponsored by the National Cancer Institute. It is charged with simplifying administrative procedures performed by Clinical Cooperative Groups.
· CTV Clinical Target Volume. The clinical target volume (CTV) is the tissue volume that contains a demonstrable GTV and/or sub-clinical microscopic malignant disease, which has to be eliminated. This volume thus has to be treated adequately in order to achieve the aim of therapy, cure or palliation.
· CXR Chest x-ray.
· CyberKnife Brand name of a machine used to deliver linear accelerator stereotactic radiosurgery.
· cyst [sist] A fluid filled sac, similar to a balloon filled with water. Cysts occurring in the brain include the arachnoid cyst, colloid cyst, dermoid cyst and epidermoid cyst.
· cytokines [sigh´ toe kynez] Part of the immune system, cytokines are biologic response modifiers. Both lymphokines and monokines are cytokines — powerful chemical substances secreted by special cells. T lymphocytes secrete lymphokines and monokines are produced by monocytes and macrophages.
· cytoreductive [SYTO re duct ive] Adjective form of cytoreduction. Literally, the reduction in the number of cells. Cytoreductive surgery is otherwise known as ‘debulking,’ and describes the surgical removal of as much as possible of a malignant tumor.
· cytostatic [sigh toe stat´ ik] Capable of inhibiting the growth and multiplication of tumor cells.
· cytotoxic [sigh toe tok´ sic] Capable of killing cells.
· cytotoxic T cells [sigh toe tok´ sic] A subset of T lymphocytes that can kill body cells transformed by cancer or infected by viruses.