Index Page Dictionary of Leukaemia and Related Diseases ACUTE LEUKAEMIA A rapidly progressive cancer of the blood of sudden onset and characterised by the uncontrolled proliferation of immature blood cells which take over the bone marrow and spill into the blood stream. If left untreated is fatal within a few weeks or months. ACUTE LYMPHOBLASTIC LEUKAEMIA (ALL) A rapidly progressing cancer of the blood affecting the type of white blood cell known as LYMPHOCYTES. Approximately 600 new cases are diagnosed every year in the UK and it is the most common form of childhood leukaemia. ACUTE MYELOID LEUKAEMIA (AML) A rapidly progressing cancer of the blood affecting immature cells of the bone marrow, usually of the white cell population. Approximately 1,600 new cases are diagnosed each year in the UK. It is much more common in adults than in children. ACUTE NON-LYMPHOCYTIC LEUKAEMIA see ACUTE MYELOID LEUKAEMIA ACUTE PROMYELOCYTIC LEUKAEMIA This is one form of acute myeloid leukaemia. The condition responds particularly well to a drug called RETINOIC ACID which causes DIFFERENTIATION of the leukaemia cells which then die. AETIOLOGY The scientific study of the factors which cause a disease e.g.environmental factors such as infections and radiation. ALKYLATING AGENTS Anti-leukaemic drugs which interact with genetic material (DNA) in such a way as to prevent division of the cells. Drugs of this type include busulphan, chlorambucil, cyclophosphamide, melphalan. See also CHEMOTHERAPY. ALLOGENEIC BONE MARROW TRANSPLANT A BONE MARROW TRANSPLANT using marrow collected from a "matched" healthy donor, usually a brother or sister. The risks associated with the transplant increase with age and 55 years of age is generally regarded as the upper limit. ALLOGRAFT see ALLOGENEIC BONE MARROW TRANSPLANT ALOPECIA The loss of hair. A side-effect of some forms of CHEMOTHERAPY or RADIOTHERAPY used to treat leukaemia and other cancers. Usually temporary. AMYLOIDOSIS Amyloidosis is not a specific disease but the term for a group of conditions in which an abnormal substance called amyloid is deposited throughout the body. Amyloid is produced by PLASMA CELLS and amyloidoisis may occur in association with MULTIPLE MYELOMA. ANAEMIA Deficiency the oxygen-carrying pigment HAEMOGLOBIN in the blood. Causes pallor, tiredness and breathlessness. ANOREXIA Loss of appetite ANTHRACYCLINES Drugs which are used in leukaemia therapy to prevent cell division by disrupting the structure of the DNA. Drugs of this type include Daunorubicin, Doxorubicin (Adriamycin), Epirubicin, Idarubicin. See also CHEMOTHERAPY. ANTIBIOTICS Drugs which kill or stop the growth of BACTERIA, for example penicillin. ANTIBODIES Naturally produced substances in the blood which destroy or neutralize specific toxins or 'foreign bodies', for example VIRUSES. They are produced by the WHITE BLOOD CELLS known as LYMPHOCYTES in response to exposure to ANTIGENS. ANTI-EMETIC A drug to prevent or alleviate the nausea and vomiting which sometimes occur as side-effects of CHEMOTHERAPY. Drugs of this type include Metoclopramide (Maxolon), Ondanestron, Zofran. ANTIGEN A substance which stimulates cells of the body's defence system to react against it by producing ANTIBODIES. ANTILYMPHOCYTE GLOBULIN ANTIBODIES which attach to and destroy LYMPHOCYTES. This may be used clinically by injection into a vein, for example in APLASTIC ANAEMIA. One form, called antithymocyte globulin, acts specifically against T-CELLS. ANTIMETABOLITES A group of anti-cancer drugs which prevent cells growing and dividing by blocking the chemical reactions required in the cell to produce DNA. Drugs of this type include 6 mercaptopurine, azathioprine, thioguanine, methotrexate. See also CHEMOTHERAPY. APLASIA Failure of production of blood cells in the bone marrow. Usually this condition affects all types of blood cells which is called APLASTIC ANAEMIA. APLASTIC ANAEMIA A rare disorder characterised by the failure of the BONE MARROW to produce blood cells. It may occur as an inherited condition (see FANCONI’S ANAEMIA) or, more often, the disease develops later in life. This is called acquired aplastic anaemia. It leads to a severe shortage of all types of blood cell causing tiredness, susceptibility to infection and serious problems with bleeding. AUTOGRAFT see AUTOLOGOUS BONE MARROW TRANSPLANT AUTOIMMUNE DISEASE Diseases caused by an individual's immune system producing ANTIBODIES against tissues of its own body. AUTOIMMUNE THROMBOCYTOPAENIA PURPURA see IDIOPATHIC THROMBOCYTOPAENIA PURPURA AUTOLOGOUS BONE MARROW TRANSPLANT (ABMT) A BONE MARROW TRANSPLANT using the patient's own BONE MARROW or PERIPHERAL BLOOD STEM CELLS which have been collected and stored at an early stage of disease. The marrow may be manipulated in the laboratory (see PURGING) to try and ensure there is no risk of contamination with leukaemia cells. This type of procedure may be carried out up to the age of 55-60 years. B LYMPHOCYTE A type of white blood cell normally involved in the production of ANTIBODIES to combat infection. BACTERIA Microscopic organisms which cause many types of infectious disease, for example pneumonia. Patients have a reduced ability to fight infections following CHEMOTHERAPY or BONE MARROW TRANSPLANTATION. This may mean that even normally harmless bacteria, for example those which are normally found on the skin, may cause serious illness. BASOPHIL A type of WHITE BLOOD CELL which is involved in allergic and inflammatory reactions. Normally present in low numbers in the blood. BASOPHILIA An increase in the number of BASOPHILS in the blood. BENCE-JONES PROTEIN A characteristic protein found in the urine of most patients with MULTIPLE MYELOMA. It is derived from the ANTIBODIES produced by the cancerous myeloma cells and can be used to help in diagnosis of the disease and to monitor the effects of treatment. BENIGN Non-cancerous growths that may or may not need to be surgically removed. BIOPSY A small sample of fresh tissue, for example LYMPH NODE or BONE MARROW, removed for laboratory analysis to establish or confirm an exact diagnosis of disease. BISPHOSPHONATE A group of drugs used in MULTIPLE MYELOMA which do not affect the disease directly but reduce the bone damage and associated pain. BLAST CELLS Immature blood-forming cells which normally represent up to 5% of the cells in the bone marrow. They are rarely seen in healthy blood. ACUTE LEUKAEMIA is characterised by over-production of abnormal blast cells which take over the bone marrow and often spill out into the blood stream. BLAST CRISIS Aggressive phase of CHRONIC MYELOID LEUKAEMIA characterised by the production of large numbers of immature cells which may be either of the MYELOID or LYMPHOID type. Clinically similar to ACUTE LEUKAEMIA and more difficult to treat than chronic phase disease. BLOOD CELLS There are three main types of CELL in the blood stream; the RED CELL, which carries oxygen, the WHITE CELL, which fights infections, and the PLATELETS, which help prevent bleeding. The correct balance between each cell type must be maintained. Production of blood cells is controlled by natural chemicals called GROWTH FACTORS which may be used in treatment. BLOOD COUNT A routine test requiring a small blood sample to estimate the number and types of cells circulating in the blood. BONE MARROW The tissue which produces the blood cells and is found within the hollow cavities of many of the bones of the body. Bone marrow contains the STEM CELLS from which all blood cells are derived. Examination of the bone marrow is an important part of the diagnosis of leukaemia and the monitoring of treatment. BONE MARROW ASPIRATE A small volume of BONE MARROW removed under local or general anaesthetic from either the hip bone (pelvis) or breast bone (sternum). The cells in the sample can then be examined under the microscope to identify any abnormality in the developing blood cells. A TREPHINE BIOPSY may be taken at the same time. BONE MARROW TRANSPLANT (BMT) A procedure used in the treatment of a variety of blood disorders including LEUKAEMIA, LYMPHOMA and sometimes MYELOMA. The patient receives very high doses of CHEMOTHERAPY and/or RADIOTHERAPY to treat the disease. This damages the BONE MARROW and makes the blood count fall. Replacement marrow is taken from a matched donor (ALLOGENEIC BONE MARROW TRANSPLANT) or from the patient themselves (AUTOLOGOUS BONE MARROW TRANSPLANT) under a general anaesthetic and returned to the patient through a vein (or CENTRAL VENOUS LINE) in a similar way to a blood transfusion. PERIPHERAL BLOOD STEM CELLS may be used instead, especially for AUTOGRAFTS. BURKITT’S LYMPHOMA A rapidly growing type of NON-HODGKIN’S LYMPHOMA which usually affects the abdomen and requires immediate treatment. CANCER Diseases due to the uncontrolled growth and division of cells; often called malignant disease or neoplasia. CANDIDA A type of FUNGUS, candida infection in the mouth (oral thrush) is a common problem for IMMUNOSUPPRESSED patients. CANNULA A tube for insertion into the body, usually into a vein, via a sharp needle-type fitting which is then withdrawn from the cannula to allow fluids to pass through the tube. CARCINOGEN A substance which has the ability to cause cells to become cancerous. CARCINOGENESIS The development of cancer. CAT SCAN (CT SCAN) Computer Assisted Tomography (CAT) is a sophisticated X-RAY technique used to produce detailed internal images of the body, particularly the chest and abdomen. The patient lies on a couch which gradually moves through the X-ray machine and the image is built up by a computer as a cross section through the body. CATHETER A hollow tube inserted into organs of the body for admitting or removing gases or liquids. For example, for the removal of urine from the bladder. CELL BIOLOGY The study of the structure, composition and function of cells. CELL MARKERS Biochemical or genetic characteristics which distinguish and discriminate between different cell types. HLA ANTIGENS are one type of cell marker. CELLS The individual units from which tissues of the body are formed. CENTRAL NERVOUS SYSTEM (CNS) The brain and spinal cord. CENTRAL VENOUS LINE A CATHETER passed through a blood vessel into a large central vein, these are used for patients undergoing intensive therapy and provide a route for taking blood samples and administering drugs without repeated needle puncture of a vein. See HICKMAN LINE and PORTACATH. CEREBROSPINAL FLUID (CSF) This fluid surrounds and protects the brain and spinal cord. Samples can be obtained by LUMBAR PUNCTURE. CHEMOTHERAPY Treatment using anti-cancer drugs. These may be used singly or in combination to kill or prevent the growth and division of cells. Although aimed at the cancer cells, chemotherapy will also unavoidably affect rapidly dividing normal cells such as in the hair and gut causing hair loss and nausea, which are usually temporary and reversible. CHROMOSOMES Chromosomes carry the 100,000 GENES which provide the inherited blue-print of each individual. In humans there are normally 23 pairs contained in the nucleus of each cell. Alterations in the number or organization of the chromosomes may play a key role in the development of cancer. CHRONIC LEUKAEMIA A cancer of the blood of gradual onset and generally of slow progression. May be diagnosed by chance following a routine blood test and prior to the appearance of clinical symptoms. CHRONIC GRANULOCYTIC LEUKAEMIA (CGL) see CHRONIC MYELOID LEUKAEMIA CHRONIC LYMPHOCYTIC LEUKAEMIA (CLL) A slowly progressing form of leukaemia, characterised by an increased number of the type of WHITE BLOOD CELLS known as LYMPHOCYTES. With about 2,700 new cases occurring each year in the UK, it is the most common form of leukaemia and occurs predominantly in late middle age onwards. It has variable symptoms and course, but may be diagnosed by chance before the patient develops any clinical symptoms of disease. CHRONIC MYELOID LEUKAEMIA (CML) A leukaemia which is initially slowly-progressing. There are approximately 500 new cases each year in the UK. It is characterised by the presence of large numbers of abnormal, mature GRANULOCYTES, circulating in the blood. Sometimes called CHRONIC GRANULOCYTIC LEUKAEMIA (CGL). CHRONIC MYELOMONOCYTIC LEUKAEMIA A form of MYELODYSPLASIA characterised by an increase in the number of circulating white blood cells of the MONOCYTE type. CLINICAL TRIAL A carefully monitored assessment of new forms of treatment. They can vary in design and size from trials of experimental treatments involving small numbers of patients to large national trials which compare variations in current therapies. A patient will always be informed when the treatment is part of a trial. CLONE A population of genetically identical cells arising from a single parent cell. Leukaemia cells originate from one original abnormal cell producing a “leukaemic clone”. CLOTTING FACTORS A group of chemical constituents of the blood (factors I to XIII) which interact to make the blood clot. CNS LEUKAEMIA Invasion of the brain or spinal cord by leukaemic cells. This may be diagnosed by examination of the surrounding CEREBROSPINAL FLUID. COAGULATION Clotting of the blood. A complex reaction depending on a series of biochemical components and PLATELETS in the blood. See CLOTTING FACTORS. "COMMON" ACUTE LYMPHOBLASTIC LEUKAEMIA (CALL) A sub-type of ACUTE LYMPHOBLASTIC LEUKAEMIA affecting cells early in the B LYMPHOCYTE lineage which accounts for about 80% of all cases of acute lymphoblastic leukaemia. CONGENITAL A term used to describe deformities or diseases which are present at the time of birth. CONSOLIDATION TREATMENT A course of treatment with anti-cancer drugs given to the patient whilst in REMISSION with the aim of killing any remaining cancerous cells. CORD BLOOD Blood obtained from the umbilical cord at the time of birth and which derives from the baby. CORD BLOOD STEM CELLS STEM CELLS recovered from CORD BLOOD which have been shown to have the capability to repopulate BONE MARROW and produce blood cells. CORTICOSTEROIDS (STEROIDS) A group of synthetic hormones including prednisone, prednisolone, methylprednisolone and dexamethasone used in the treatment of some LEUKAEMIAS and MYELOMA. Also used to suppress graft rejection and GRAFT VERSUS HOST DISEASE following BONE MARROW TRANSPLANT. Side-effects include an increased risk of infection. CYCLOSPORIN A A drug used to prevent and treat rejection and GRAFT VERSUS HOST DISEASE in transplant patients by suppressing their normal immune system. CYTOGENETICS The study of the structure of CHROMOSOMES. Cytogenetic tests are carried out on samples of blood and BONE MARROW taken from leukaemia patients to detect any chromosomal abnormalities associated with the disease. These help in the diagnosis and selection of optimal treatment. CYTOMEGALOVIRUS A VIRUS which is harmless in healthy people but may cause serious disease in severely IMMUNOSUPPRESSED patients. Particularly dangerous following a BONE MARROW TRANSPLANT. CYTOPAENIA A reduction in the number of cells circulating in the blood. CYTOTOXIC DRUGS Anti-cancer drugs which act by killing or preventing the division of cells. See CHEMOTHERAPY. DELETION A CHROMOSOME abnormality in which part of a single chromosome has been lost. DEPLETION A laboratory procedure for reducing the numbers of specific cell types within BONE MARROW donated for transplantation, for example the removal of some types of LYMPHOCYTES. This may be to avoid "mismatch" problems (particularly in relation to unrelated donor transplants) or to remove a sub-set of potentially leukaemic cells in an AUTOGRAFT. DIFFERENTIATION The gradual maturation of a cell whereby its functions and properties become increasingly specialised. Leukaemic cells are often poorly differentiated, i.e. they show immature characteristics. DISSEMINATED DISEASE Disease in which the cancerous cells have spread from the tissue of origin to other organs. DIURETIC A drug to stimulate the excretion of urine by the kidneys. May be used during CHEMOTHERAPY to ensure the excretion of anti-cancer drugs. DNA (Deoxyribonucleic acid) Provides the essential building block for storing genetic material. There are 4 different chemical components of DNA (bases) arranged in coded sequence as GENES which determine an individual's inherited characteristics. DONOR LYMPHOCYTE INFUSION If a patient who has had an ALLOGENEIC BONE MARROW TRANSPLANT has a relapse, with return of the original disease, they may be given LYMPHOCYTES from the donor. This may eliminate the leukaemia cells. DOWN’ S SYNDROME A congenital condition in which some or all of the body cells have three copies of CHROMOSOME 21. This form of TRISOMY is associated with an increased risk of leukaemia. EOSINOPHIL A type of WHITE BLOOD CELL involved in inflammatory, allergic or anti-parasitic responses. Usually present in the circulation in very low numbers. EOSINOPHILIA Increased numbers of EOSINOPHILS circulating in the blood. It occurs in some cases of HODGKIN'S DISEASE, in asthma, hay fever and parasitic infections, HYPEREOSINOPHILIC SYNDROME and EOSINOPHIL LEUKAEMIA. EOSINOPHIL LEUKAEMIA Some patients with high eosinophil counts and abnormal bone marrow are classed as having eosinophil leukaemia. It may not always be obvious whether the diagnosis should be eosinophil leukaemia or HYPEREOSINOPHILIC SYNDROME. Some doctors consider eosinophil leukaemia to be a form of CHRONIC MYELOID LEUKAEMIA (CML). EPIDEMIOLOGY The science of studying the occurrence of disease in populations and relating this to genetic and/or environmental causes. EPSTEIN BARR VIRUS A common VIRUS which causes glandular fever. Also associated with BURKITT’S LYMPHOMA. There is some evidence of a link between Epstein-Barr virus infection and HODGKIN’S DISEASE. ERYTHROCYTE see RED BLOOD CELL ERYTHROLEUKAEMIA A rare cancer of the blood affecting immature red blood cells. This is a sub-type of ACUTE MYELOID LEUKAEMIA. ESSENTIAL THROMBOCYTHAEMIA A rare condition related to POLYCYTHAEMIA RUBRA VERA characterised by the production of large numbers of abnormal PLATELETS. Symptoms include HAEMORRHAGE, THROMBOSIS and enlargement of the SPLEEN. Treatment varies according to the severity of the disease. EXTRA NODAL LYMPHOMA Literally "outside the LYMPH NODES", but exhibiting the characteristics of lymph node cancer. A term used to describe the extent and site of disease. FANCONI ANAEMIA A rare inherited type of APLASTIC ANAEMIA which carries an increased risk to the patient of developing leukaemia. May be treated by a BONE MARROW TRANSPLANT. FOLIC ACID A form of vitamin B obtained from green leafy vegetables, e.g. spinach. It is essential for synthesis of DNA and therefore the growth and division of cells. FUNGUS An infective agent such as a mould or yeast, causing particular problems in IMMUNOSUPPRESSED patients. See CANDIDA. FOLIC ACID ANTAGONIST A chemical which inhibits a cell's capacity to use FOLIC ACID and so prevent cell division, for example methotrexate. See also CHEMOTHERAPY. GAMMA GLOBULIN A concentrated solution of ANTIBODY given through a vein to fight infections, e.g. measles in patients with low resistance. GAMMOPATHY Normally the GAMMA GLOBULINS which make up ANTIBODIES are a mixture of a huge number of different types. When nearly all gamma globulin being produced is one particular form this is called MONOCLONAL GAMMOPATHY. GENES Formed from DNA and carried on the CHROMOSOMES, genes direct the activities of cells. They are responsible for the inherited characteristics which distinguish one individual from another. Each human individual has an estimated 100,000 separate genes. GRAFT REJECTION Rarely, when a patient has an ALLOGENEIC BONE MARROW TRANSPLANT, the new bone marrow will fail to start producing blood cells. This is called graft rejection. It may be possible to do a second transplant. GRAFT VERSUS HOST DISEASE (GVHD) A common, and serious, complication of BONE MARROW TRANSPLANTATION. Some of the donor's immune cells reject the patient's own cells as foreign. The skin, liver and gut may be affected. It can occur in either chronic or acute forms and is treatable by IMMUNOSUPPRESSIVE drugs. GRAFT VERSUS LEUKAEMIA (GVL) If GRAFT VERSUS HOST DISEASE is present but not severe it may be beneficial in helping to kill off leukaemia cells. If all the T-LYMPHOCYTES are removed from an ALLOGENEIC BONE MARROW TRANSPLANT it minimizes the risk of graft versus host disease but increases the risk of RELAPSE. GRANULOCYTE A type of WHITE BLOOD CELL. They protect the body against infection by seeking out and killing micro-organisms. GROWTH FACTORS A complex family of proteins produced by the body to control growth, division and maturation of blood cells by the BONE MARROW. Some are available as products of genetic engineering, and are used clinically to stimulate normal white cell production following CHEMOTHERAPY or BONE MARROW TRANSPLANTATION. GROWTH HORMONE A biochemical secreted by a gland in the brain which controls growth and is of particular importance during adolescence. RADIOTHERAPY given to the head and neck of children with leukaemia may lead to a deficiency in growth hormone. This may be replaced by INTRAVENOUS INJECTIONS. HAEMATOCRIT see PACKED CELL VOLUME HAEMATOLOGIST A doctor specialising in the diagnosis and treatment of blood diseases. HAEMATOLOGY The study of blood diseases including leukaemia. HAEMATOPOIESIS Term to describe the production and maturation of blood cells from very primitive stem cells. This takes place in the BONE MARROW which is a spongy tissue in the middle of bones. HAEMOGLOBIN The iron containing pigment in RED BLOOD CELLS which carries oxygen around the body. Lack of haemoglobin is called ANAEMIA. Normal values are between 12-18 grams per 100 ml of blood. HAEMOPOIESIS see HAEMATOPOIESIS HAEMORRHAGE Bleeding either to the outside through the skin or internally. HAIRY CELL LEUKAEMIA A rare leukaemia related to CHRONIC LYMPHOCYTIC LEUKAEMIA and characterised by the presence of abnormal cells with "hair- like" projections. It occurs in middle age onwards. Treatment may involve removal of the SPLEEN. Current therapy includes the use of INTERFERON and, more recently, new CYTOTOXIC drugs. HEPATITIS Inflammation of the liver. HEPATOMEGALY Enlargement of the liver. HICKMAN LINE A narrow plastic tube or CATHETER which is inserted, under anaesthetic, into a major blood vessel in the chest. It is used for patients undergoing intensive therapy and provides a route for taking blood samples and administering drugs without repeated needle puncture of a vein. HISTIOCYTOSIS Histiocytes are cells produced in the bone marrow and assist in recognising invading bacteria and parasites. Histiocytes are normally found in skin, liver, lung, gut, lymphatic glands, spleen, bones and parts of the brain but in histiocytosis they wander elsewhere in the body. HISTOLOGY The investigation of tissue samples by chemical and microscopical analysis. HLA ANTIGENS A complex family of genetically inherited proteins which are found on the surface of cells throughout the body. They determine the "match" between patient and potential donor in BONE MARROW TRANSPLANTATION. HLA factors are inherited from the mother and father and so the greatest chance of having the same HLA type is between brothers and sisters, that is 1 in 4. HODGKIN’S DISEASE A type of LYMPHOMA. There are approximately 1,300 new cases per year in the UK. HTLV Human T cell Lymphotropic VIRUS. A family of viruses which invade T cells. Includes a rare leukaemia virus, HTLV-1, found primarily in Japan and the Caribbean causing an increased incidence of T cell leukaemias in these populations. The family also includes the AIDS causing-virus, HIV. HYPERCALCAEMIA Increased levels of calcium in the blood. It is often associated with MULTIPLE MYELOMA due to degradation of the bones. It is dangerous if not controlled. HYPEREOSINOPHILIC SYNDROME In some patients the number of EOSINOPHILS In the blood is markedly and persistently raised with no obvious cause such as a parasite infection. These patients have either hypereosinophilic syndrome (HES) or EOSINOPHIL LEUKAEMIA. IATROGENIC DISEASE A disease produced as a consequence of medical or surgical treatment. IDIOPATHIC Term applied to diseases to indicate that their cause is unknown. IDIOPATHIC THROMBOCYTHAEMIA PURPURA (ITP) A rare disorder characterised by an acute shortage of PLATELETS with resultant bruising and spontaneous bleeding. Anti-platelet ANTIBODIES are detectable in some cases. It may present in either an acute or a chronic form. IMMUNE DEFICIENCY Impaired ability of the body's defence mechanisms to combat infections by BACTERIA, VIRUSES and FUNGI. IMMUNE RESPONSE The reaction of the body to an ANTIGEN, for example an infectious agent, or to the tissues of another individual as in the rejection of an organ transplant. IMMUNOGLOBULINS Proteins in the blood PLASMA which function as ANTIBODIES and play an important part in controlling infections. IMMUNOSUPPRESSION A treatment induced reduction in the body's defence mechanisms. Deliberate immunosuppression is a necessary part of the BONE MARROW TRANSPLANT procedure to prevent GRAFT VERSUS HOST DISEASE and GRAFT REJECTION. INDUCTION TREATMENT see REMISSION INDUCTION INTENSIFICATION Increasing the amount, number or combination of anti-cancer drugs given to a patient in an attempt to kill drug-resistant or residual leukaemic cells. INTERFERONS A family of proteins derived from human cells and involved in fighting viral infections. They are now available as products of genetic engineering for use in the treatment of a number of leukaemias and leukaemia related diseases including HAIRY CELL LEUKAEMIA, CHRONIC MYELOID LEUKAEMIA and APLASTIC ANAEMIA. INTRAMUSCULAR INJECTION Injection into the muscle. INTRATHECAL INJECTION Injection of drugs into the spinal fluid to prevent or treat CNS LEUKAEMIA or LYMPHOMA. INTRAVENOUS INFUSION The giving of ANTIBIOTICS, blood products, anti-cancer drugs or nutrients into a patient's vein over a prolonged period of time. INTRAVENOUS INJECTION The giving of drugs into a vein through a syringe. IN VITRO Literally meaning "in glass". Used to describe studies carried out on living cells or tissues grown in the laboratory. IN VIVO In living tissue or in a whole organism. KARYOTYPE Analysis to check the number, form and structure of CHROMOSOMES. This can give valuable information to aid in the diagnosis and the selection of treatment. KARYOTYPIC ABNORMALITY Abnormality in the number, form or structure of CHROMOSOMES. Particular abnormalities are associated with particular sub-types of leukaemia. LARGE GRANULAR LYPHOCYTIC LEUKAEMIA Large granular lymphocytic leukaemia (LGL) is a chronic leukaemia which affects T-cells. LGL is a rare disease with important clinical differences from CHRONIC LYMPHOCYTIC LEUKAEMIA. LATE EFFECTS Results of CHEMOTHERAPY and/or RADIOTHERAPY which only become apparent with long-term monitoring of the patient over a period of years. These are of particular concern in patients below the age of puberty. LEUKAEMIA From the Greek meaning "white blood". Often referred to as cancer of the blood. Characterised by the widespread uncontrolled proliferation of large numbers of abnormal blood cells, usually of the white cell lineages, which take over the BONE MARROW and often spill out into the blood stream. Other organs that may also be affected include LYMPH NODES, SPLEEN, liver. LEUKAEMOGENESIS The development of leukaemia. LEUKAPHERESIS Method of separating blood into its liquid and cellular components and for the removal of WHITE BLOOD CELLS before returning the remainder of the blood to the patient. It is used to reduce the white cell count when CHEMOTHERAPY is to be avoided, for example during pregnancy. LEUKOCYTES Collective term for WHITE BLOOD CELLS. LEUKOPAENIA Condition in which the number of white cells in the blood is greatly reduced. Leads to increased risk of infections. LINEAGE Describes cells with a common ancestry, that is developing from the same type of identifiable immature cell. LI-FRAUMENI SYNDROME An inherited family trait carrying an increased risk of cancer during childhood and early adulthood. LONG -TERM SURVIVAL Term used to describe the survival of LEUKAEMIA patients who have been disease free for prolonged periods of time, usually at least five years. The chance of disease returning (RELAPSE) decreases with time. LUMBAR PUNCTURE A procedure for removing spinal fluid from around the spinal cord using a fine needle in the lower part of the back. Samples are analysed for evidence of any CNS LEUKAEMIA. Also used to administer anti-cancer drugs to either prevent or cure CNS disease. LYMPH NODES or GLANDS Small structures found throughout the body, e.g. neck, groin, armpits, abdomen, which contain both mature and immature LYMPHOCYTES. LYMPHATIC SYSTEM This consists of the SPLEEN, LYMPH NODES and areas of LYMPHOID tissue such as the tonsils. It plays a major part of the body’s IMMUNE RESPONSE. LYMPHOCYTE A type of white blood cell which is involved in the immune defences of the body. There are two main types - B-CELLS and T-CELLS. LYMPHOID Referring to the lymphatic system including LYMPHOCYTES and LYMPH NODES. LYMPHOMA A cancer which originates in lymphoid tissue, including the lymph glands, liver, SPLEEN, bowel and BONE MARROW. The disease results from the uncontrolled production of LYMPHOCYTES. The general term includes about a dozen different forms of the disease but there are two main categories: HODGKIN’S DISEASE and NON-HODGKIN’S LYMPHOMA. LYMPHOPROLIFERATION An increase in the production of LYMPHOCYTES. This may occur as a normal response to infection. MACROGLOBULINAEMIA In certain conditions, such as WALDENSTROM’S MACROGLOBULINAEMIA, affected LYMPHOCYTES produce an excess amount of an abnormal ANTIBODY known as IgM for Macroglobulin. MACROPHAGE A type of WHITE BLOOD CELL which migrates from the blood into tissues and acts as a scavenger, ingesting particles such as BACTERIA. MAGNETIC RESONANCE IMAGING A body scanning technique which uses an intense magnetic field to generate images of the internal organs. Properties of normal and cancerous tissue differ, allowing malignant tumours to be visualised by computer processing of the signals detected. MAINTENANCE TREATMENT Treatment given for a period of months or years to maintain REMISSION and eliminate any residual leukaemic cells in the body, usually for ACUTE LYMPHOBLASTIC LEUKAEMIA. MALIGNANCY A term applied to tumours characterised by the uncontrolled proliferation of cells. See also CANCER. MAST CELL LEUKAEMIA The mast cell is related to the monocyte/macrophage cells of the immune system and is found in most tissues. Excessive production of mast cells may be seen in the conditions systemic mastocytosis and mast cell leukaemia. MEGAKARYOCYTE Large cell in the BONE MARROW which produce PLATELETS. MONOCLONAL Proteins made by cells which all belong to the same CLONE are identical and are called monoclonal. MONOCLONAL ANTIBODIES ANTIBODIES made by cells belonging to a single CLONE. Current research is investigating their clinical application for targeted delivery of drugs to leukaemic cells and to purify cells used for bone marrow and stem cell transplants. MONOCLONAL GAMMOPATHY OF UNKNOWN SIGNIFICANCE Different types of GAMMA GLOBULIN are produced to deal with different infections. Exclusive production of one form of gamma globulin is called monoclonal GAMMOPATHY. If there is no evidence of disease such as MYELOMA or LYMPHOMA to explain the presence of a monoclonal gammopathy it is called Monoclonal Gammopathy of Unknown Significance (MGUS). MONOCYTE A type of WHITE BLOOD CELL of relatively large size which acts as a scavenger and ingests large particles. MONOCYTIC LEUKAEMIA Cancer of the blood due to proliferation of cells of the MONOCYTE series. MONOSOMY Term which indicates the loss of a whole CHROMOSOME. MRC (MEDICAL RESEARCH COUNCIL) Government funded body "to promote the balanced development of medical and related biological research" in the UK. It organises national CLINICAL TRIALS for the assessment of new treatment protocols for leukaemia and some of the related diseases. MUCOSITIS Inflammation of the mouth and throat which may be caused by anti-leukaemia drugs. MULTI-DRUG RESISTANCE Multi-drug resistance occurs when leukaemia cells eliminate anti-cancer drugs before a high enough concentration to kill the cells is achieved. Resistance against most drugs will make the leukaemia very difficult to treat. MULTIPLE MYELOMA A cancer caused by uncontrolled proliferation of the WHITE BLOOD CELLS called PLASMA CELLS within the bone marrow. The malignant cells do not usually accumulate in the blood and the tumour growth is restricted to the bones. This leads to bone destruction and is often associated with kidney problems. MUTATION A minute genetic change to DNA, for example by exposure to hazardous chemicals or copying errors during cell division. If these affect normal cell function it can lead to disease development. MYELOBLASTIC Immature cells of the MYELOID series. MYELODYSPLASIA OR MYELODYSPLASTIC SYNDROMES (MDS) A group of closely linked conditions in which the process of blood cell formation is disturbed by a failure of the immature cells to grow and develop normally. Sometimes referred to as "PRELEUKAEMIA", although only a minority of patients will ever develop LEUKAEMIA. Treatment may be based on supportive therapy or involve the use of anti-cancer drugs. MYELOFIBROSIS A disease in which the bone marrow is taken over by fibrous tissue and is no longer able to produce adequate numbers of mature blood cells. Often accompanied by enlargement of the spleen. It is occasionally found in cases of ACUTE MYELOID/ACUTE LYMPHOID/CHRONIC MYELOID LEUKAEMIA. The primary form is classified as a MYELOPROLIFERATIVE disorder. MYELOID Collective term for the non-LYMPHOCYTE groups of WHITE BLOOD CELLS. It includes cells from the GRANULOCYTE, MONOCYTE and PLATELET lineages. MYELOMA see MULTIPLE MYELOMA MYELOMONOCYTIC A condition which affects both the MYELOID and MONOCYTIC cells. MYELOPOIESIS The process of production and maturation of MYELOID cells. See HAEMATOPOIESIS MYELOPROLIFERATIVE DISORDERS A group of disorders characterised by the over- production of blood cells by the bone marrow. One or more of the cell lineages may be involved and treatment varies according to the type and severity of the disease. See ESSENTIAL THROMBOCYTHAEMIA, POLYCYTHAEMIA RUBRA VERA. MYELOSCLEROSIS see MYELOFIBROSIS NEUROPATHY Damage to the nerves which may occur as a complication of anti-leukaemia treatment. It usually affects the peripheral nerves (nerves to the arms and legs) and may be reversible when when treatment is stopped or reduced. NEUTROPAENIA A condition in which the NEUTROPHIL count is reduced. It may be caused by high dose chemotherapy and carries an increased risk of infection. NEUTROPHIL The most common type of cell within the GRANULOCYTE group of WHITE BLOOD CELLS. NON-HODGKIN’S LYMPHOMA A group of LYMPHOMAS which differ in important ways from HODGKIN’S DISEASE and are classified according to the microscopic appearance of the cancer cells. The disease is classified as either indolent (slowly growing) or aggressive (rapidly growing) and may be treated in a variety of ways depending on the exact diagnosis. ONCOGENES GENES carrying the potential to cause cancer. ONCOLOGIST A specialist in the diagnosis and treatment of cancer. PACKED CELL VOLUME Measurement of the proportion of the blood occupied by the red blood cells. Normal values are 40-54% in males, 35-47% in females. PALLIATIVE CARE Treatment aimed at relieving symptoms and pain rather than effecting a cure. PANCYTOPAENIA Condition in which there are reduced numbers of all types of blood cells. PARAPROTEIN (MALIGNANT) Malignant paraprotein is a form of ANTIBODY characteristic of, and produced by, malignant cells of the mature B-CELL type, for example in MULTIPLE MYELOMA. Its presence in the blood acts as an important marker of disease. PAROXYSMAL NOCTURNAL HAEMOGLOBINURIA (PNH) A rare disorder characterised by an increased rate of break- down of RED BLOOD CELLS and decreased production of WHITE BLOOD CELLS and PLATELETS. This leads to excretion of the red blood pigment, HAEMOGLOBIN, in the urine, particularly at night. The cause is unknown and the severity of disease variable. PATHOGENESIS Development of a disease. PATHOLOGIST A doctor who specialises in the cause and diagnosis of disease and how disease affects the organs of a body. PERIPHERAL BLOOD STEM CELL There are small numbers of STEM CELLS in the circulation. These are known as Peripheral Blood Stem Cells. (PBSC) PERIPHERAL BLOOD STEM CELL TRANSPLANT The use of PERIPHERAL BLOOD STEM CELLS as an alternative to BONE MARROW TRANSPLANTATION. The STEM CELLS are obtained by using GROWTH FACTORS to increase numbers in the circulation to a level where they can be harvested. PETECHIAE Small red or purple pin-head spots on the skin. They are small HAEMORRHAGES and usually the result of a shortage of PLATELETS. PHARMACOKINETICS The study of the action of a drug in the body over a period of time, including the processes of absorption, metabolism and excretion. PHENOTYPE The characteristic appearance and function of a cell or tissue. PHILADELPHIA CHROMOSOME An abnormal CHROMOSOME associated with CHRONIC MYELOID LEUKAEMIA and some cases of ACUTE LYMPHOBLASTIC LEUKAEMIA. The Philadelphia chromosome is formed when part of chromosome 9 attaches to chromosome 22. This abnormality is found in nearly all cases of chronic myeloid leukaemia. PLASMA CELLS Large cells derived from the LYMPHOCYTES that form ANTIBODIES. Not normally found in circulating blood but restricted to BONE MARROW and LYMPH NODES. PLASMA CELL LEUKAEMIA The end stage of MYELOMA when immature PLASMA CELLS are found circulating in the blood. PLASMACYTOMA A localised area of MYELOMA-like disease, either in a bone or in the other tissues of the body. If there is only one such area it is called solitary plasmacytoma. PLATEAU PHASE Stable stage of disease in MULTIPLE MYELOMA following good response to anti-cancer treatment. PLATELETS Tiny cell-like bodies derived from MEGAKARYOCYTES in the bone marrow. Circulate in the blood and play an important role part in the prevention and control of bleeding. Normal values, 150-400 x 109 per litre. POLYCYTHAEMIA RUBRA VERA (PRV) A condition characterised by the over-production of RED BLOOD CELLS by the BONE MARROW. Diagnosis is based on an increased number and volume of red cells. The total number of WHITE BLOOD CELLS and PLATELETS may also be increased. Treatment will vary according to the age of the patient and severity of the disease. This condition carries an increased risk of developing ACUTE LEUKAEMIA. PORTACATH A form of CENTRAL VENOUS LINE in which the whole of the line is surgically implanted within the body, unlike a HICKMAN LINE. A membrane just below the skin gives access by a simple skin puncture to a line running straight into one of the main blood vessels. This simplifies the administration of CHEMOTHERAPY. PRELEUKAEMIA A general term referring to some non-cancerous blood disorders, such as MYELODYSPLASIA which carry an increased risk of the patient developing ACUTE LEUKAEMIA. The expression is misleading because only a minority of patients with these conditions develop leukaemia. PROGENITOR CELL or PRECURSOR CELL Immature cell in the BONE MARROW which is responsible for producing mature blood cells. PROGNOSIS An assessment of the likely benefits of treatment for a patient, particularly concerning the chances of cure and complete recovery. PROLYMPHOCYTE An early LYMPHOCYTE precursor. Not commonly seen in the blood but in PROLYMPHOCYTIC LEUKAEMIA they may be present in large numbers. PROLYMPHOCYTIC LEUKAEMIA A variant of CHRONIC LYMPHOCYTIC LEUKAEMIA in which the malignant cells have a more immature appearance. The disease requires CHEMOTHERAPY and/or RADIOTHERAPY and sometimes removal of the spleen (SPLENECTOMY). PROPHYLAXIS Precautionary treatment given with the aim of preventing a disease occurring. PROTOCOL A schedule of treatment. For example, the number, frequency and timing of administration of a course of anti-cancer drugs. PRURITIS Itching, sometimes severe, which may be a significant problem in LYMPHOMA. PURGING The laboratory treatment of BONE MARROW harvested for an AUTOLOGOUS BONE MARROW TRANSPLANT or PERIPHERAL BLOOD STEM CELL transplant to remove any residual leukaemic cells in order to reduce the theoretical chance of RELAPSE. The use of this procedure varies between treatment centres and depends on the type of leukaemia being treated. PURPURA A condition characterised by the occurrence of purple spots on the skin, often accompanied by bleeding from the gums. RADIOLOGY The use of X-RAYS in the diagnosis of a disease. RADIOTHERAPY The use of X-RAYS and other forms of radiation in treatment. It kills cancer cells in the area of the body being treated and is therefore effective treatment for localised disease, particularly in LYMPHOMA and MULTIPLE MYELOMA. Side-effects vary according to the type of treatment and will be discussed with the patient by the hospital staff. RAI SYSTEM A system for classification of CHRONIC LYMPHOCYTIC LEUKAEMIA based on the symptoms, if any, and on laboratory tests. It is used to decide whether to start treatment. RECOMBINANT A term used to describe drugs which have been produced using the techniques of genetic engineering. The products are exact equivalents of compounds produced naturally by the body. RED BLOOD CELLS The cells of the blood which contain the red pigment HAEMOGLOBIN and carry oxygen to all the tissues of the body. Normal red cell count in the blood, 4.5-5.0 x 1012 per litre. REED-STERNBERG CELL A distinctive abnormal cell seen in HODGKIN’S DISEASE. REFRACTORY ANAEMIA A form of MYELODYSPLASIA which primarily affects red cell production by the BONE MARROW. In some cases the developing red cells show an internal ring of iron granules. These cells are called SIDEROBLASTS. Refractory anaemia (RA) and refractory anaemia with sideroblasts (RAS) are the most common forms of MYELODYSPLASIA. REFRACTORY ANAEMIA WITH EXCESS BLASTS (RAEB) A form of MYELODYSPLASIA characterised by the build up of immature white blood cells (BLASTS) in the bone marrow.If the immature cells are particularly numerous it may indicate a chance of transformation to ACUTE LEUKAEMIA and the condition is called RAEB in transformation (RAEBt). RELAPSE The recurrence of disease. In LEUKAEMIA this may be indicated by changes in the blood, bone marrow, CNS or testicle even before the patient experiences any symptoms. REMISSION Restoration of the blood, BONE MARROW and general health of the patient to normal. Induced by CHEMOTHERAPY and/or RADIOTHERAPY. REMISSION INDUCTION The initial course of treatment given to patients on admission to hospital to remove all clinically detectable cancer. RETICULOCYTES Immature red blood cells normally restricted to the BONE MARROW and present in the blood stream in very low numbers (0.2-2%). An increase in numbers indicates increased proliferation in the bone marrow, for example following CHEMOTHERAPY. RETINOIC ACID A synthetic compound related to vitamin A which can stimulate cells to become fully mature. It may be used clinically to treat some forms of leukaemia, notably a sub-type of ACUTE MYELOID LEUKAEMIA called ACUTE PROMYELOCYTIC LEUKAEMIA. RETROVIRUS A type of VIRUS which is related to the AIDS virus. One rare form of human leukaemia is caused by the HTLV-1 retrovirus.. RICHTER’S SYNDROME Development of LYMPHOMA in a patient who has CHRONIC LYMPHOCYTIC LEUKAEMIA. RNA (Ribonucleic acid) A copy of the genetic code used by cells as a template for making proteins. It copies the message given out by the DNA. SECONDARY LEUKAEMIA A leukaemia arising from either previous CHEMOTHERAPY or RADIOTHERAPY or as the development of a pre-existing condition, such as MYELODYSPLASIA. SEPTICAEMIA This is a general term to describe serious bacterial infection of the blood stream often associated with high fever. SERUM The part of the blood which remains after cells, PLATELETS and fibrinogen have been removed, usually by allowing the blood to clot. SIBLING Brother or sister. SIDEROBLASTS see REFRACTORY ANAEMIA SPLEEN The spleen acts as a “discriminating filter” of the blood. It can selectively remove old RED BLOOD CELLS and BACTERIA and other foreign bodies. The spleen also acts as a store for PLATELETS. It is often enlarged in leukaemia. SPLENECTOMY Surgical removal of the spleen. This is sometimes done in LEUKAEMIA or LYMPHOMA as part of a patients treatment. SPLENOMEGALY Enlargement of the SPLEEN. STAGING An assessment of the spread of disease through the body, for example in LYMPHOMA. It is of importance for the selection of optimal treatment. STEM CELLS The most primitive cells in the BONE MARROW from which all the various types of blood cell are derived. STEROIDS see CORTICOSTEROIDS SUBCUTANEOUS INJECTION An injection into tissue immediately under the skin. SYNGENEIC Literally “sharing the same genes”. It refers to BONE MARROW or PERIPHERAL BLOOD STEM CELL transplants between identical twins. T-LYMPHOCYTE A type of WHITE BLOOD CELL derived from the THYMUS (hence T cells) involved in controlling immune reactions. Uncontrolled proliferation of this type of cell gives rise to T cell leukaemia/lymphoma. TESTICULAR RELAPSE Recurrence of LEUKAEMIA in the testicles. The disease may be restricted to the testicles or may also show evidence of disease in either the BONE MARROW or CNS. Treatment will depend on the timing and extent of relapsed disease. THROMBOCYTE see PLATELET THROMBOCYTHAEMIA An over-production of platelets. See also ESSENTIAL THROMBOCYTHAEMIA. THROMBOCYTOPAENIA Shortage of PLATELETS leading to problems with bleeding. THROMBOSIS The development of a clot in a blood vessel, usually in a vein but sometimes in an artery. Potentially life-threatening if left untreated. THYMUS A gland at the base of the neck concerned with the production of functional T CELLS. TOMOGRAPHY An X-RAY picture of internal organs of the body. TOTAL BODY IRRADIATION (TBI) RADIOTHERAPY often given in several doses prior to BONE MARROW TRANSPLANTATION with the aim of killing any residual leukaemia in the patient. It is used in conjunction with high dose anti-cancer drugs. The procedure and its side-effects will be discussed individually with the patient. TRANSFORMATION A term to describe either the change of a normal cell into a cancerous cell, or the acceleration of disease in CHRONIC MYELOID LEUKAEMIA from the chronic to a more acute phase characterised by the production of large numbers of BLAST CELLS. TRANSLOCATION A CHROMOSOME abnormality in which the part of one chromosome has become transferred to another. See also PHILADELPHIA CHROMOSOME. TREPHINE BIOPSY Removal of a small "core" of BONE MARROW under local anaesthetic. It is used to assess bone marrow structure, the number and distribution of all the blood cell types. The trephine biopsy is normally done at the same time as a BONE MARROW ASPIRATE. TRISOMY Term which indicates the presence of an additional whole CHROMOSOME. TUMOUR An accumulation of abnormal cells which may be BENIGN or MALIGNANT. ULTRASONOGRAPHY (ULTRASOUND) Pictures of the body's internal organs built up from the interpretation of reflected sound waves. VINCA ALKALOIDS Anti-cancer drugs originally derived from Vinca (periwinkle) plants. Drugs of this type include vincristine, vinblastine. See also CHEMOTHERAPY. VIROLOGY The study of VIRUSES and viral diseases. VIRUS A minute infective agent which depends on the cell it infects for its replication and survival. WALDENSTROM’S MACROGLOBULINAEMIA A rare disorder which has features in common with an indolent NON-HODGKIN’S LYMPHOMA and with MULTIPLE MYELOMA. The progression of the condition more closely resembles indolent non-Hodgkin’s lymphoma. WHITE BLOOD CELLS (LEUKOCYTES) They comprise several different types of cells within three main types: GRANULOCYTES, LYMPHOCYTES and MONOCYTES. They are formed in the BONE MARROW and it is their uncontrolled proliferation which leads to LEUKAEMIA. Normal values are within the range 4 .5 - 11.0 x 109 per litre. X RAYS A form of radiation used both in diagnosis, for example STAGING of LYMPHOMA and MULTIPLE MYELOMA, and treatment (see RADIOTHERAPY). ZIG (ZOSTER IMMUNE GLOBULIN) GAMMA GLOBULIN against the chicken pox virus which can be given to an IMMUNOSUPPRESSED patient following direct contact with the disease to prevent infection. © Leukaemia Research Fund, 1998 Return to LRF Home