A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
Absolute lymphocytosis:
The presence of more than 15,000 lymphocytes in a cubic millimetre of blood.
Acute:
Sudden onset of disease symptoms.
Alkylating agents:
Anticancer drugs that can damage DNA of cells, leading to cell death.
Allogeneic bone marrow transplantation:
A procedure in which a patient receives bone marrow from a compatible, though not genetically identical donor.
Alopecia:
Loss of hair, be it on the head or all over the body. Alopecia can be caused by certain chemotherapy drugs.
Anemia:
A below-normal number of red blood cells.
Antibodies:
Proteins produced by certain white blood cells in response to the presence of foreign substances (antigens). Each antibody can bind to only one specific antigen. The purpose of this binding is to help destroy that antigen.
Antigen:
Any substance that the body regards as foreign. When introduced into the body, and antigen causes the immune system to produce a corresponding antibody to fight it.
Antimicrobial therapy:
Treatment to kill micro-organisms (such as bacteria or fungi) or to suppress their growth.
Aplastic anemia:
A form of anemia that occurs when the bone marrow fails to produce adequate numbers of blood cells.
Apheresis:
Collection of peripheral blood stem cells by a device similar to a dialysis machine. The blood may be taken from a Hickman or other type of catheter or, if the patients veins are good, from the arms. Gathering enough cells for an autologous stem cell transplant may take from one to five days, depending on the amount of stem cells the patient has in their blood.
Apoptosis:
Programmed cell death. If apoptosis is affected, the cell well not die, causing a malignant or cancerous condition.
Aspirate:
To remove material from a body cavity by suction through a needle. Also refers to material that is removed this way.
Asymptomatic:
Without symptoms.
Autoimmune disease:
Diseases caused by an individual's immune system producing antibodies against tissues of its own body.
Autologous bone marrow transplantation:
A procedure in which bone marrow that had been removed from a patient is given back to that patient.
Axillary lymph node:
A lymph node found in the armpit (axilla).

B cells:
White blood cells, also know as B lymphocytes, that develop in the bone marrow and are capable of producing antibodies.
Basophil:
A type of white blood cell. Basophils are one type of granulocyte.
Biological response modifier (BRM):
A substance that boosts, directs, or restores the body's normal immune (defense) system. An example is interferon. BRM's are produced naturally in the body and can also be manufactured in the laboratory.
Blast cell:
A very immature blood cell.
Blood-brain barrier:
A network of blood vessels located around the central nervous system with very closely spaced cells that make it difficult for potentially toxic substances-including anticancer drugs-to penetrate the blood vessel walls and enter the spinal cord.
Bone marrow:
The soft, spongy tissue in the centre of many bones; it produces white blood cells, red blood cells and platelets.
Bone marrow aspiration:
The removal of a sample of fluid and cells from the bone marrow for examination under a microscope. Aspiration is done with a needle. The results of the examination tell the doctor whether cancer cells are present.
Bone marrow biopsy:
The removal of a sample of solid tissue from the bone marrow for examination under a microscope. The results of the examination tell the doctor whether cancer cells are present.
Bone marrow harvest:
The removal and collection of bone marrow, usually done prior to a bone marrow transplant but sometimes done as a preventive measure in case of relapse.
Bone marrow transplantation (BMT):
A procedure in which doctors replace marrow destroyed by high doses of anticancer drugs and/or radiation.
Bone marrow suppression:
A decrease in the number of blood cells produced which may be a result of treatment or tumor invasion of the bone marrow.

Candida:
A type of fungus. Candida infection in the mouth (oral thrush) is a common problem for immunosuppressed patients.
Cell surface marker:
An identifying substance on the surface of cells.
Central nervous system (CNS):
The brain and the spinal cord.
Chromosome:
A structure in the nucleus of a cell containing DNA, which transmits genetic information, Normally, 46 chromosomes appear as a long thread inside each human cell.
Chronic:
Lasting for a long period of time or marked by frequent recurrence.
Clinical trial:
Medical research conducted with volunteers. Each trial is designed to answer scientific questions and to find better ways to prevent or treat disease.
Clotting episodes:
the inappropriate development of blood clots due to disease.
Colony-stimulating factors (CSF's):
Proteins that stimulate the development of cells in the bone marrow.
Committed cells:
Cells that have matured sufficiently that microscopic examination can reveal what type of cell they will be when fully matured.
Complementary therapy:
Techniques or approaches often used in addition to standard treatment. Examples are diet and meditation.
Complete remission (CR):
the disappearance of all signs and symptoms of disease.
Conditioning:
Treatment with high-dose chemotherapy, and sometimes with high-dose radiation therapy, to prepare a patient for bone marrow transplantation or peripheral blood stem cell transplantation.
Congenital:
Present at birth.
Corticosteroids:
Complex chemical compounds produced in the outer layer of the adrenal gland, which is located near the kidney. They are important in regulating body chemistry. Corticosteroids can be manufactured in the laboratory and used as drugs.
Cytogenetics:
The study of the structure of chromosomes. Cytogenetic tests are carried out on leukemia patients to detect any chromosomal abnormalities associated with the disease. This helps in diagnosis and selection of optimal treatment.
Cytokines:
Hormones or growth factors produced by cells that help regulate cell processes.
Cytoplasm:
The fluid, liquid, or "watery" part of a cell; the cytoplasm surrounds the nucleus of the cell.

Differentiation:
The process in which cells mature and become specialized.
DNA:
Deoxyribonucleic acid; nucleic acid is present in all living cells. DNA contains the genetic information of the cell.

Endemic:
Constantly present in a population.
Eosinophil:
A type of white blood cell. Eosinophils are one type of granulocyte.
Epidemiology:
the study of the factors that determine how diseases are distributed in a community.
Engraftment:
The process in which transplanted bone marrow or peripheral blood stem cells begin to grow in the bone marrow of the host and to manufacture new white blood cells, red blood cells, and platelets.
Erythrocytes:
Red blood cells.
Etiology:
The cause of a disease.

Fibrous:
Containing fibres (threadlike noncellular structures). When bone marrow becomes fibrotic, it can be difficult to obtain a bone marrow sample.
Five-year survival rate:
The percentage of people with a given cancer who are expected to survive five years or longer with the disease. Five-year survival rates, while statistically valid, should not be seen as a predictor in individual cases.
Frequency:
The number of times a wave pattern repeats.

Genetic:
Inherited; having to do with information that is passed from parents to their children through DNA.
Graft:
Tissue taken from one person (donor) and transferred to another person (recipient) or taken from one part of a person's body and transferred to another part of the same person's body.
Graft-versus-host disease:
A condition that may develop after allogeneic bone marrow transplantation; the transplanted marrow (graft) attacks the patient's (host's) organs.
Graft-versus-leukemia (GVL):
A reaction of donated bone marrow or peripheral stem cells against a patient's own leukemia cells.
Granulocyte:
A type of white blood cell. Neutrophils, eosinophils, and basophils are granulocytes.
Granulocyte colony-stimulating factor (G-CSF):
A growth factor that promotes the production and development of granulocytes.
Group C status:
A designation for investigational anticancer drugs that are effective against one or more forms of cancer but have not been approved for general marketing by the U.S. Food and Drug Administration. Doctors may obtain Group C drugs from the National Cancer Institute to treat patients who would benefit from their use.

Hematocrit:
the percentage of blood that consists of red blood cells. Sometimes expressed as packed cell volume (PCV).
Hematologist:
A doctor who specializes in studying and treating diseases of the blood.
Hematology:
The study of blood, blood producing organs, and blood disorders.
Hematopoiesis:
The formation and development of blood cells.
Hemoglobin:
The protein found in red blood cells that carries oxygen. Hemoglobin gives blood its red colour.
Hepatomegaly:
Enlargement of the liver.
Hepatosplenomegaly:
Enlargement of the liver and spleen.
Hickman Catheter:
A catheter that is inserted into a large vein near the heart and which is used for delivery of medications and transfusions.
Hodgkin's disease:
A malignant disease of the lymph nodes characterized by painless enlargement of lymphatic tissues and the spleen. Symptoms often include fever, weight loss, anemia, and night sweats. Named for the doctor who first identified it.
Host:
In the case of an organ or bone marrow transplantation, the recipient of the organ or marrow.
Human leukocyte antigens (HLAs):
A set of six antigens used to match a blood or bone marrow donor to a recipient. These antigens appear on white blood cells as well as cells of almost all other tissues and are analogous to red blood cell antigens (type A, B, O, etc.). By typing for HLA antigens, donors and recipients of white blood cells, platelets, and organs can be matched to ensure good performance and survival of transfused and transplanted cells. A perfect HLA match occurs only between identical twins.

Idiopathic:
Having no known cause.
Immune response:
The activity of the immune system against foreign substances (antigens).
Immunoglobulin:
A specific protein substance that is produced by plasma cells to aid in fighting infection. Examples include IgG, IgM, IgA, IgD and IgE.
Immunoglobulin therapy:
Treatment with antibodies to prevent infection.
Immunophenotyping:
Determining what kind of surface molecules are present on cells. Used by pathologists to determine the exact type of leukemia from a blood sample.
Immunosuppressant:
A drug (such as chemotherapy) or other factor that prevents the immune system from reacting to foreign substances and fighting disease.
Immunosuppression:
Suppression of the immune response as a result of drugs (chemotherapy) or radiation.
Immunotherapy:
Treatment of disease by inducing, enhancing, or suppressing an immune response.
In vitro:
In an artificial environment. Literally meaning "in glass". Used to describe studies carried out on living cells or tissues grown in the laboratory.
In vivo:
In the living body. Used to describe a process or reaction occurring therein.
Incidence:
The number of new cases of a specific disease occurring during a given time period.
Indolent:
Characterized by slow progression--a disease process or a tumor of low malignancy.
Interferon:
A protein produced by various cells in the body. Large quantities of different interferons may be produced in the laboratory. These proteins are used in the treatment of some forms of cancer. Interferon is a type of biological response modifier.
Interleukins:
Proteins that carry regulatory signals between blood-forming cells. Large quantities of interleukins can be produced in the laboratory and used to treat some forms of cancer. Interleukins are biological response modifiers.
Intrathecal:
Into the fluid around the brain and spinal cord -- a way of injecting drugs.
Intravenous:
Into a vein -- a way of injecting drugs.
Ions:
Atoms or groups of atoms that have an electrical charge.

Leukapheresis:
A blood filtering process used to remove extra lymphocytes.
Leukemia:
Cancer that begins in developing cells in the bone marrow. Leukemia occurs when immature or mature cells multiply in an uncontrolled manner in the bone marrow. It is classified as lymphocytic or myeloid, according to the type of cell that is multiplying abnormally, and either acute, signifying rapidly progressing disease with a predominance of highly immature (blastic) cells, or chronic, which denotes slowly progressing disease with greater numbers of more mature cells
Leukocytes:
White blood cells.
Leukocytosis:
An increase in the number of leukocytes in the blood.
Leukopenia:
A below-normal number of white blood cells.
Lymph:
The almost colourless fluid that bathes the body tissues and carries cells that help fight infection.
Lymph nodes:
Small bean-shaped structures in the lymphatic system. The lymph nodes store special cells that can trap bacteria or cancer cells travelling through the body in lymph.
Lymphadenopathy:
Disease of the lymph nodes.
Lymphatic system:
The tissues and organs (including the bone marrow, spleen, thymus, and lymph nodes) that produce and store cells that fight infection and the network of vessels that carry lymph.
Lymphocytes:
A type of white blood cell.
Lymphoma:
Cancer of the lymphatic system, which is composed of the tissues and organs that produce and store cells that fight infection and disease. The lymphatic system includes the bone marrow, spleen, thymus, lymph nodes, and a network of vessels that carry fluid and infection-fighting cells. Lymphomas fall into two categories: Hodgkin's Disease and Non-Hodgkin's lymphomas.

Marrow fibrosis:
The development of fibrous tissue in the bone marrow. Marrow fibrosis interferes with blood cell production.
Median age:
In a list of ages arranged from youngest to oldest, the median age is in the centre; half of the ages in the list are below the median and half are above it.
Medullary:
In the central or inner portion; the medullary portion of the bone is the bone marrow.
Metabolism:
A general term for the physical and chemical processes and reactions to them taking place in the body. These processes are primarily concerned with the way nutrients are used in the body.
Metastasis:
The spread of cancer cells to other areas of the body through the lymphatic system or the bloodstream.
Monoclonal antibodies:
Antibodies specific for a single antigen. They can be produced in large quantities in the laboratory. Monoclonal antibodies are being studied in clinical trials to determine their effectiveness in cancer detection, diagnosis, and treatment.
Monocytes:
One type of white blood cell. Monocytes (macrophages) play a key role in phagocytosis. The also interact with lymphocytes to regulate the immune response.
Mononuclear cells:
Monocytes and lymphocytes; white blood cells other than granulocytes.
Morbidity rate:
The frequency of the appearance of complications following a surgical procedure or other treatment.
Morphology:
The science of forms and structures of organisms; the form and structure of a particular organism, organ, or part.
Mucositis:
Inflammation of the mouth and throat, which may be caused by anti-leukemia drugs.
Mutagenic:
Causing a permanent change in genetic material (DNA).
Myelodysplastic syndromes:
Conditions that result when blood cells fail to form or reproduce normally.
Myeloid:
A collective term for the non-lymphocyte groups of white blood cells. It includes cells from the granulocyte, monocyte, and platelet lineages.
Myeloproliferative disorders:
A group of diseases characterised by the abnormal excess growth of cells in the bone marrow.

Neoplasm:
An abnormal growth (tumor) that starts from a single altered cell; a neoplasm may be benign or malignant. Cancer is a malignant neoplasm.
Neutropenia:
A below-normal number of neutrophils.
Neutrophils:
A type of white blood cell (also known as a polymorphonuclear neutrophils or PMNs). Neutrophils are a type of granulocyte and are a primary defence against bacterial invasion.
Night sweats:
Profuse sweating of the body during the night.
NK (natural killer) cells:
Large lymphocytes that attack certain cells on contact and probably help regulate the immune system.
Non-Hodgkin's lymphoma:
A cancer of the lymphatic system. What distinguishes non-Hodgkin's lymphoma from Hodgkin's lymphoma is the absence of a type of cell called the Reed-Sternberg cell. This cell is present only in Hodgkin's lymphoma. The treatment methods for Hodgkin's and non-Hodgkin's lymphomas are very different.
Nuclear:
Having to do with the nucleus of a cell. The nucleus is considered the control centre of a cell.
Nuclei:
Plural of nucleus.
Nucleus:
The part of a cell that contains genetic information. The nucleus is considered the control centre of the cell.

Oncogene:
A type of gene that is normally inactive. When these genes are "turned on" (activated), they cause normal cells to change into cancer cells.
Oncogenic:
Capable of causing cancer.
Oncologist:
A doctor who specializes in studying and treating cancer.
Opportunistic:
An organism capable of causing disease only in a host whose resistance is lowered--usually by other diseases or by drugs

Palliative care:
Treatment that relieves symptoms, such as pain, but is not expected to cure the disease. The main purpose is to improve the patient's quality of life.
Partial remission:
The reduction, but not complete disappearance, of cancer in response to therapy.
Peripheral blood:
Blood circulating throughout the body.
Petechiae:
Tiny red spots under the skin; often a symptom of leukemia.
Phagocytosis:
The process by which phagocytes (literally, cell eaters) surround and destroy micro-organisms or any foreign matter.
Pheresis:
A procedure in which blood is removed from a donor, separated, and a portion retained, with the remainder being returned to the donor.
Philadelphia chromosome:
A abnormality of chromosome 22 that is seen in the bone marrow and blood cells of most patients with chronic myelogenous leukemia and some with acute lymphocytic leukemia. Also called Ph1.
Plasma:
The liquid portion of the blood.
Plasma cells:
Large cells derived from the lymphocytes that form antibodies. Plasma cells are normally restricted to the bone marrow and lymph nodes and are not found in circulating blood.
Platelets:
Blood cells that help to control bleeding by inducing clotting. Also called thrombocytes.
Pneumocystosis:
Pneumonia resulting from infection with Pneumocystis carinii, frequently seen in immunologically compromised or steroid-treated individuals.
Prognosis:
The probable outcome or course of a disease; the chance of recovery.
Prolymphocytic leukemia:
A variant of chronic lymphocytic leukemia in which the malignant cells have an more immature appearance.
Prophylaxis:
An attempt to prevent disease.
Protein:
A compound that is an essential part of plants and animals.
Purging:
Removal of tumour cells from harvested bone marrow or blood before autologous transplantation.

Radiation therapy:
Treatment with high-energy rays to kill cancer cells. Also called radiotherapy.
Radiologist:
A doctor who specializes in using radiation to diagnose or treat disease.
Refractory:
Not responding favourably to treatment.
Relapse:
The reappearance of signs and symptoms of disease after treatment.
Relative survival rate:
A survival rate that takes normal life expectancy into account; the likelihood that a patient will not die of his or her disease by some specified time after diagnosis.
Remission:
A period in which there is no evidence of disease on physical examination or examination of the bone marrow and blood.
Rescue process:
The infusion of harvested bone marrow or peripheral blood stem cells into a patient who has undergone high-dose therapy.
Respiration:
Breathing; the exchange of oxygen and carbon dioxide between the atmosphere and the body's cells.
Retrovirus:
One of a large group of RNA viruses that are capable of copying and transferring genetic material.
Richter's syndrome:
Transformation of CLL to diffuse large cell lymphoma.
RNA:
Ribonucleic acid; nucleic acid present in all living cells. RNA controls protein synthesis by transplanting the genetic information within the cell.

Secondary leukemia:
Leukemia (most often AML) that arises when bone marrow is damaged by chemotherapy given to treat certain types of cancer or other diseases.
Spleen:
An organ on the left side of the abdomen near the stomach that plays an important role in immune system activities. It produces lymphocytes, filters the blood, stores blood cells, and destroys those that are ageing. It is part of the lymphatic system.
Splenectomy:
Surgical removal of the spleen.
Splenomegaly:
Enlargement of the spleen.
Spinal tap:
A procedure in which a needle is inserted into the space surrounding the spinal cord in order to withdraw cerebrospinal fluid. The cerebrospinal fluid is then analyzed in a laboratory for evidence of disease. Also called a lumbar puncture.
Stem cells:
The immature cells from which all blood cells develop. These cells may divide to form more stem cells or mature into a variety of blood cell types.
Syngeneic bone marrow transplantation:
Grafting between two genetically identical individuals (identical twins).
Systemic:
Affecting the body as a whole.

T cells:
White blood cells that are important in the body's immune system. Also known as T lymphocytes, they mature in the thymus.
Thrombocytes:
Platelets.
Thrombocytopenia:
A below-normal number of platelets in the blood.
Thrombocytosis:
A condition in which too many platelets are found in the blood.
Thymus:
A small gland located in the top of the chest, behind the breastbone and between the lungs. The thymus plays a major part in the immune system.
Tumor burden:
The amount of cancer cells that are present in the body.

Uric acid:
A waste product created when the body digests and uses food and liquids.

X-ray:
High-energy radiation used in low doses to diagnose diseases and in high doses to treat cancer.

Copyright© 2000, 1999 David M. Thomas.