B-cells / B-lymphocytes: White blood cells formed in the bone-marrow by hematopoietic stem cells; precursors of antibody-forming terminally differentiated plasma cells. B-cells carry immunoglobulin and class II MHC antigens on their cell surfaces. Waldenstrom’s macroglobulinemia is a disorder of the B-cells.

BDR: An abbreviation for a treatment combination consisting of bortezomib (Velcade), dexamethasone, and rituximab (Rituxan).

Bence-Jones proteins: Abnormal two-unit (dimers) complexes of immunoglobulin light chains found in the urine of some patients, particularly those with multiple myeloma and Waldenstrom’s macroglobulinemia.

Bendamustine (Treanda): A drug that is used to treat chronic lymphocytic leukemia (CLL) and slow-growing B-cell non-Hodgkin’s lymphomas (NHL) such as Waldenstrom’s macroglobulinemia. Bendamustine damages the DNA in cancer cells and cause them to die. It is a type of alkylating agent and a type of antimetabolite.

Benda-R or B-R: An abbreviation for a chemoimmunotherapy treatment combination consisting of bendamustine (Treanda) and rituximab (Rituxin).

Beta-2-microglobulin: Cell membrane associated protein (part of the class I major histocompatibility complex molecule) that is specifically elevated in inflammation, renal disease, AIDS, and in some cancers, including Waldenstrom’s macroglobulinemia, chronic lymphocytic leukemia, and multiple myeloma. Urine levels of beta-2-microglobulin can be affected by kidney disease.

Bing-Neel syndrome: A condition that involves infiltration of the central nervous system (brain and spinal cord) by Waldenstrom’s macroglobulinemia cells and/or IgM deposition, or as a result of hyperviscosity syndrome.

Bone marrow: Spongy tissue occupying the hollow central cavity of bones that is the site of hematopoiesis. Following puberty, the marrow located in the spine, ribs, breastbone, hip, shoulders, and skull is most active in blood cell formation. In the adult, the bones of the hands, feet, legs and arms do not contain marrow in which blood cells are made. In these sites, the marrow is filled with fat cells.

Bone marrow aspiration: A bone marrow aspiration is the removal by needle of fluid and cells from the bone marrow.

Bone marrow biopsy (BMB): A bone marrow biopsy is the removal of soft tissue, called bone marrow, from inside bone. Bone marrow is found in the hollow part of most bones. The sample is usually taken from the hip bone.

Bone marrow microenvironment: The immediate neighborhood of the cells in the bone marrow; comprises cells that facilitate the survival, differentiation, and proliferation of hematopoietic cells.

Bone marrow transplant: A bone marrow transplant is a procedure to replace damaged or destroyed bone marrow with healthy bone marrow stem cells. There are three kinds of bone marrow transplants. The first is the autologous bone marrow transplant (“auto” means “self”) where stem cells are removed before the patient receives high-dose chemotherapy or radiation treatment. After these treatments are done, stems cells are given back to the patient. The second is the allogeneic bone marrow transplant (“allo” means “other”) where stem cells are removed from another person, called a donor. Most times, the donor must have the same or similar genetic makeup as the patient, so that he or she is a “match” to the recipient. Special blood tests are done to determine if a donor is a good match, and a brother or sister is most likely to be a good match. However, sometimes parents, children, and other relatives may be good matches. Donors who are not related to the patient may be found through national bone marrow registries. The third kind of bone marrow transplant is the umbilical cord blood transplant where stem cells are removed from a newborn baby’s umbilical cord immediately after being born. The stem cells are stored until they are needed for a transplant. Umbilical cord blood cells are so immature that there is less of a concern that they will not match.

Bortezomib (Velcade): A drug used for the treatment of multiple myeloma and certain types of lymphoma, including Waldenstrom’s macroglobulinemia. It is in the drug class called proteasome inhibitors.

Bruton’s tyrosine kinase (BTK): An enzyme important in the development and activation of B-cells; it is over-expressed in Waldenstrom’s macroglobulinemia and is targeted by a drug called ibrutinib (Imbruvica).

Bruton’s tyrosine kinase (BTK) inhibitor: Any drug that suppresses the expression of Bruton’s tyrosine kinase; ibrutinib (Imbruvica) is one example.

CAR T-cell therapy: This is based on the principle that the T-cells in one’s own body can be used to seek out and kill cancer cells. In this type of therapy, receptors on the surface of one’s T-cytotoxic cells can be modified in the laboratory to recognize certain specific antigens on one’s tumor cells – these engineered T-cells are called chimeric antigen receptor (CAR) T-cells. They are grown in large quantities in the laboratory and then reinfused into the patient, where they seek out and destroy the tumor.  This type of therapy is still being tested in clinical trials and is not yet available clinically.

CaRD: An abbreviation for a treatment combination consisting of carfilzomib (Kyprolis), rituximab (Rituxan), and dexamethasone.

Carfilzomib (Kyprolis): A newer member in the family of drugs called proteasome inhibitors that are used for the treatment of multiple myeloma and certain types of lymphoma, including Waldenstrom’s macroglobulinemia.

Chemoimmunotherapy: The use of chemotherapy combined with immunotherapy. Chemotherapy uses drugs to kill or slow the growth of cancer cells; immunotherapy uses treatments such as monoclonal antibodies, growth factors, and vaccines to stimulate or restore the ability of the immune system to fight cancer. A common chemoimmunotherapy regimen is CHOP combined with rituximab, so-called R-CHOP.

Chemotherapy: Often just called chemo, this is a treatment with one or more of a specific group of anti-cancer drugs such as fludarabine, cyclophosphamide, CHOP, or CVP. Traditional chemotherapy agents are cytotoxic and act on cells that divide rapidly, one of the main properties of most cancer cells. They can also harm normal cells that divide rapidly, including cells of the bone marrow, digestive tract, and hair follicles. Even if a single chemo drug is given, it is often combined with pre-medicating drugs to reduce the side-effects of the main drug.

Chlorambucil (Leukeran): A drug used to treat several types of leukemias and lymphomas.  It blocks cell growth by damaging the cell’s DNA and kills cancer cells.  It is a type of alkylating agent.

CHOP: An abbreviation for a chemotherapy combination that is used to treat non-Hodgkin’s lymphoma and other types of cancer. It includes the drugs Cytoxan, hydroxydoxorubicin (also known as Doxorubicin or Adriamycin), Oncovin (also known as vincristine), and prednisone.

Chromosomes: Thread-like structures inside the nucleus of each cell that package the DNA. There are 23 pairs of chromosomes in most human body cells (except eggs and sperm), for a total of 46 chromosomes.

Chronic lymphocytic leukemia (CLL): Chronic lymphocytic leukemia is a type of cancer of the blood and bone marrow, the spongy tissue inside bones where blood cells are made. The term “chronic” in chronic lymphocytic leukemia comes from the fact that it typically progresses more slowly than other types of leukemia. The term “lymphocytic” refers to the cells affected by the disease – a group of white blood cells called lymphocytes which help the body fight infection. Chronic lymphocytic leukemia most commonly affects older adults.

Cladribine (2CdA / Leustatin): An anticancer drug that belongs to the family of drugs called nucleoside analogs.

Clinical trial: A type of research study that tests how well new medical approaches work in people. These studies test new methods of screening, prevention, diagnosis, or treatment of a disease.

Clone: One of more of a group of genetically identical cells derived by reproduction from a single parent.

Cluster of differentiation (CD): Cluster of differentiation is a system used for the identification and investigation of cell surface molecules present on leukocytes and platelets initially but found in almost any kind of cell of the body, providing targets for immunophenotyping and for treatment with monoclonal antibodies. Also, these markers are often used to associate cells with certain immune functions. While using one CD molecule to define populations is uncommon (though a few examples exist), combining markers has allowed for cell types with very specific definitions within the immune system (i.e., the “cluster” of differentiation).

CD20: Cluster of differentiation molecule B-lymphocyte antigen CD20 or just CD20 is expressed on the surface of all B-cells beginning at the pro-B phase and progressively increasing in concentration until maturity. The protein has no known natural ligand, and its function is to enable optimal B-cell immune response, specifically against T-independent antigens. It is suspected that it acts as a calcium channel in the cell membrane. CD20 is the target of the monoclonal antibodies rituximab, Iiritumomab tiuxetan, and tositumomab, which are all active agents in the treatment of all B-cell lymphomas and leukemias (like Waldenstrom’s macroglobulinemia).

Cold agglutinin disease (CAD): An autoimmune hemolytic anemia caused by autoantibodies that bind to red blood cells at temperatures reached in the capillaries of the skin and subcutaneous tissues, causing red blood cell destruction (hemolysis). The antibodies are monoclonal in origin, having either kappa or lambda light chains but not both, and are seen in certain patients with Waldenstrom’s macroglobulinemia.

Combination therapy: Treatment that uses more than one drug or modality.

Comorbidity: The condition of having two or more diseases at the same time.

Complete blood count (CBC): A complete blood count is a test panel requested by a doctor or other medical professional that gives information about the cells in a patient’s blood. The cells that circulate in the bloodstream are generally divided into three types; white blood cells (leukocytes), red blood cells (erythrocytes), and platelets (thrombocytes). Abnormally high or low counts may indicate the presence of many forms of disease, and hence blood counts are amongst the most commonly performed blood tests in medicine, as they can provide an overview of a patient’s general health status.

Red blood cell count: A red blood cell count is a useful blood test that can provide information about how many red blood cells are in a person’s blood as one component of a complete blood count.

White blood cell count: The white blood cell count is used as part of a full complete blood count to screen for a wide range of diseases and conditions; to help diagnose an infection or inflammatory process; to determine the presence of other diseases that affect white blood counts such as allergies, leukemia or immune disorders, to name a few; to monitor the progression of conditions such as those named above; to monitor the body’s response to various treatments, and/or to monitor bone marrow function.  Some treatments, such as radiation and chemotherapy, are known to affect white blood cells and may be monitored using white blood cell counts.

Complete response (CR): In Waldenstrom’s macroglobulinemia, a complete response following treatment is defined as the absence of serum monoclonal IgM by immunofixation, normal serum IgM level, complete resolution of enlarged lymph nodes and enlarged spleen if present at baseline, and normal bone marrow aspirate and biopsy.

Comprehensive metabolic panel (CMP): A panel of 14 blood tests which serves as an initial broad screening tool for physicians, nurse practitioners, and physician assistants. Because it is often ordered as a routine part of an annual physical examination or check-up, over time the CMP provides an important baseline of a patient’s basic physiology. Any changes or abnormal results, and in particular combinations of abnormal results, thus provide important initial data for differential diagnosis, in which case more specialized tests may be indicated. In and of itself, however, the CMP provides an important gross check on the status of kidney function, liver function, and electrolyte and fluid balance.  In addition to being used at routine physicals of healthy patients, the CMP is routinely administered to monitor the status of a patient with a chronic disease

Constitutional symptoms: Constitutional symptoms refer to a group of symptoms that can affect many different parts of the body. Examples include weight loss, fevers, fatigue, and malaise. Other examples include chills, night sweats, and decreased appetite. Generally, they are very nonspecific, with a vast number of diseases and conditions as potential causes, thereby requiring further evaluation for any diagnosis.

Computerized axial tomography (CT or CAT) scan: Commonly called a CAT scan, this is an X-ray procedure that uses a computer to produce a detailed picture of a cross section of the body. Adding intravenous contrast material helps outline blood vessels and kidney function, whereas oral contrast helps better define organs such as the stomach and intestines.

Cryoglobulin(s): Abnormal proteins detected in the laboratory by chilling serum to below 32 degrees Celsius where the proteins become insoluble. At a normal body temperature of 37 degrees Celsius, cryoglobulins are soluble. Serum specimens from patients with cryoglobulins must be kept warm until testing.

Cryoglobulinemia: Clinical disease characterized by cryoglobulins in the serum; often associated with immune complex antigen-antibody (cryoprecipitable immunocomplex) deposits in the kidneys and other tissues. Three types of cryoglobulinemia have been described: Type I (monoclonal cryoglobulinemia); Type II (mixed cryoglobulinemia) was first noted in Waldenstrom’s macroglobulinemia, and can be seen as well is seen in auto-immune disorders; Type III (mixed polyclonal-polyclonal cryoglobulinemia) can be seen with auto-immune diseases, infections, and other medical diseases.

CVP: An abbreviation for a chemotherapy combination used to treat slow-growing forms of non-Hodgkin’s lymphoma (NHL) and chronic lymphocytic leukemia (CLL). It includes the drugs Cytoxan, Oncovin (also called vincristine), and prednisone.

CXCR4: A chemokine that is important in the homing of stem cells to the bone marrow.  Mutations in CXCR4 have recently been identified in approximately 25-30% of patients with Waldenstrom’s macroglobulinemia and may impact the clinical presentation and overall survival in patients with the disease.

Cyclophosphamide (Cytoxan): A drug used to treat many types of cancer; it attaches to DNA in cells and kills cancer cells.  It is a type of alkylating agent.

Cytokines (lymphokines): A generic term for non-antibody proteins released by one cell population which act as intercellular mediators, as in the generation of an immune response.

Cytopenias: Lower-than-normal numbers of blood cells.  See leukopenia, lymphopenia, neutropenia, and thrombocytopenia.

Deoxyribonucleic acid (DNA): Deoxyribonucleic acid is a nucleic acid containing the genetic instructions used in the development and functioning of all known living organisms (with the exception of ribonucleic acid viruses). The deoxyribonucleic acid segments carrying this genetic information are called genes. Likewise, other deoxyribonucleic acid sequences have structural purposes, or are involved in regulating the use of this genetic information. Along with ribonucleic acid and proteins, deoxyribonucleic acid is one of the three major macromolecules that are essential for all known forms of life.

Dexamethasone: A synthetic steroid (similar to steroid hormones produced naturally in the adrenal gland). Dexamethasone is used to treat leukemia and lymphoma and may be used to treat some of the problems caused by other cancers and their treatment.

Diffuse large B-cell lymphoma (DLBCL): A cancer of B-cells, it is the most common type of non-Hodgkin’s lymphoma in adults. It is an aggressive cancer that usually arises from normal B-cells, but it can also represent a malignant transformation from another type of leukemia or lymphoma. It is most commonly characterized by rapidly enlarging lymph nodes, fever, weight loss, and night sweats.

DRC: An abbreviation for a chemoimmunotherapy treatment combination consisting of dexamethasone, rituximab (Rituxan), and cyclophosphamide (Cytoxan).

Efficacy: Effectiveness; the ability of a treatment to produce the desired result.

Epigenetics: The study of inherited changes in phenotype (appearance) or gene expression caused by mechanisms other than changes in the DNA.  These changes may remain through cell divisions for the remainder of the cell’s life and may also last for multiple generations.  However, there is no change in the underlying DNA sequence of the organism; instead, non-genetic factors (stress, environment, diet) cause the organism’s genes to behave differently.

Erythrocyte sedimentation rate (ESR): The erythrocyte sedimentation rate, also called a sedimentation rate or Westergren erythrocyte sedimentation rate, is the rate at which red blood cells settle to the bottom of a test tube in a period of 1 hour. It is a common hematology test and is a non-specific measure of inflammation.

Erythrocytes (red blood cells / RBCs): The blood cells that contain hemoglobin. Hemoglobin binds oxygen when red blood cells pass through the lung and releases it to the tissues of the body. The red blood cells make up a little less than half the volume of blood in healthy individuals.

Erythropoietin: A hormone produced mainly by the kidneys that is required for the normal production of red blood cells. Released into the bloodstream in response to decreased levels of oxygen in the blood (as in anemia), erythropoietin (EPO) interacts with the EPO receptor on red blood cell progenitors to increase production of red blood cells. Epoetin alfa (Epogen, Procrit) and darbepoetin alfa (Aranesp) are laboratory-made forms of the human hormone EPO that can be used to treat anemia.

Everolimus (RAD001 or Afinitor): A drug that inhibits mammalian target of rapamycin (mTOR) and is used for the treatment of relapsed Waldenstrom’s macroglobulinemia.

Extramedullary disease: manifestation of a lymphoid mass outside of the bone marrow.  In some Waldenstrom’s macroglobulinemia patients, tissue masses do occur in such regions.

FISH (fluorescence in situ hybridization) analysis: A laboratory technique used to look at genes and chromosomes in cells and tissues.  Pieces of DNA that contain a fluorescent dye are made in the laboratory and added to cells or tissues on a glass slide.  When these pieces of DNA bind to specific genes or areas of chromosomes on the slide, they light up when viewed under a microscope with a special light.

Flow cytometry: Flow cytometers can also use antibodies tagged with fluorescent stains that bind to specific antigens on the cell surfaces.  When a stain is added to the cell sample, a laser beam excites the cells so that they fluoresce and emit a specific color of light, depending of the type of stain used.

Fludarabine (Fludara): The active ingredient in a drug used to treat chronic lymphocytic leukemia (CLL) and non-Hodgkin’s lymphomas, including Waldenstrom’s macroglobulinemia.  Fludarabine blocks cells from making DNA and kills cancer cells. It is a type of nucleoside analog.

Follicular lymphoma (FL): Follicular lymphoma is the most common of the indolent non-Hodgkin’s lymphomas and the second-most-common form of non-Hodgkin’s lymphoma overall. It is defined as a lymphoma of follicle center B-cells (centrocytes and centroblasts), which has at least a partially follicular pattern. It is positive for the B-cell markers CD10, CD19, CD20, and CD22 but almost always negative for CD5.

Funduscopic exam: The examination of the back of the eye (fundus) with an ophthalmoscope; it allows a magnified evaluation of the blood vessels, nerves, and retina.

Gene: A region of DNA that controls a hereditary trait in an individual.

Genome sequencing: Any method or technology for determining the order of DNA found in the genes of an individual.

Exome sequencing: A technique for sequencing only the protein-coding genes in a genome. It consists of first selecting only the subset of DNA that encodes proteins (knowns as exons) and then sequencing that DNA. There are 180,000 exons in a human genome, or approximately 1% of the total DNA; mutations that affect the exons are much more likely to have severe consequences than those in the remaining 99% of the human genome.

Whole genome sequencing: A technique that determines the complete DNA sequence of a genome.

Graft vs. host disease (GVHD): A reaction of white blood cells in transplanted tissue (the graft) against the tissues of the recipient (the host).

Granulocytes: White blood cells that attack and destroy bacteria. (See neutrophils.)

Granulocyte-colony stimulating factor (G-CSF): A class of cytokines which controls the differentiation of hematopoietic stem cells to granulocytes such as neutrophils and natural killer cells (e.g. Neupogen, Neulasta).

Heavy chains: Heavy chains are the large polypeptide subunits of a protein complex. These are the larger of the two types of chains that comprise a normal immunoglobulin or antibody molecule.

Hematocrit (Hct): A measure of red blood cells as a percentage of whole blood.

Hematologist / oncologist: A hematologist-oncologist is a doctor with special training in the diagnosis and treatment of blood diseases, especially blood cell cancers. This type of doctor is trained in hematology (the study of blood) and oncology (the study of cancer).

Hematology: Hematology, also spelled haematology, is the branch of biology, physiology, internal medicine, pathology, clinical laboratory work, and pediatrics that is concerned with the study of blood, the blood-forming organs, and blood diseases.

Hematopoiesis: The process of blood formation.

Hematopoietic stem cells (HSCs): Residing in the bone marrow, these are the single common ancestor to all the functional cells found in the blood and immune cells. The stem cells represent less than 0.01% of bone marrow cells in adults, and give rise to a larger, intermediately differentiated population of progenitor cells. These progenitor cells in turn divide and differentiate further through several stages into mature cells responsible for specific tasks. These stem cells are also able to re-create themselves through self-renewal. This potential for unlimited life span and future proliferation is their most important defining property.

Hemoglobin (Hb): Hemoglobin is the iron-containing oxygen-transport protein in the red blood cells of almost all vertebrates as well as the tissues of some invertebrates. Hemoglobin in the blood carries oxygen from the respiratory organs (lungs or gills) to the rest of the body (i.e. the tissues) where it releases oxygen to metabolize nutrients and provide energy to power the functions of the organism; hemoglobin also collects the resultant carbon dioxide to bring it back to the respiratory organs to be released from the organism.

Hemolysis: Hemolysis is the rupturing of erythrocytes (red blood cells) and the release of their contents (hemoglobin) into surrounding blood plasma.

Hemolytic: Relating to or involving or causing hemolysis.

Hemolytic anemia: A form of anemia due to hemolysis of erythrocytes (red blood cells), either in the blood vessels (intravascular) or elsewhere in the human body (extravascular). It has numerous possible causes, ranging from relatively harmless to life-threatening. Hemolytic anemia is either inherited or acquired. Treatment depends on the cause and nature of the hemolysis.

Hepatic: Refers to the liver.

Hepatosplenomegaly: Hepatosplenomegaly is the simultaneous enlargement of both the liver (hepatomegaly) and the spleen (splenomegaly). Hepatosplenomegaly can occur as the result of blood disorders, lymphoma, acute viral hepatitis, infectious mononucleosis, and histoplasmosis (also known as “Spelunker’s Lung”) or it can be the sign of a serious and life threatening lysosomal storage disease. Systemic venous hypertension can also increase the risk for developing hepatosplenomegaly, which may be seen in those patients with right-sided heart failure.

Hyperviscosity: Excessive blood thickness.

Hyperviscosity syndrome: A group of symptoms triggered by increase in the viscosity of the blood.  Symptoms include spontaneous bleeding from mucous membranes, visual disturbances, and neurologic symptoms ranging from headache, dizziness, and vertigo to seizures and coma.

Hypogammaglobulinemia: A type of immune deficiency characterized by a reduction in immunoglobulins (A, G, M, etc.)

Ibrutinib (Imbruvica): An oral drug that targets Bruton’s tyrosine kinase (BTK), an enzyme which is important in the development and activation of B-cells and which is over-expressed in Waldenstrom’s macroglobulinemia (WM). It is the first, and so far only, drug FDA-approved for the treatment of WM.

Idelalisib (Zydelig): An oral drug that acts as an inhibitor of phosphoinositide 3-kinase. It is used in chronic lymphocytic leukemia and is being tested in patients with Waldenstrom’s macroglobulinemia.

Immune system: An immune system is a system of biological structures and processes within an organism that protects against pathogens. To function properly, an immune system must detect a wide variety of injuries or infectious agents, including viruses, bacteria, and parasites, and distinguish them from the organism’s own healthy tissue and processes. Also, pathogens can rapidly evolve and adapt to avoid detection and destruction by the immune system. As a result, multiple layer defense mechanisms have also evolved to recognize and neutralize pathogens. These layers start with the surface of the organism. If a pathogen breaches these barriers, the innate immune system provides an immediate, but non-specific response. If pathogens successfully evade the innate response, the adaptive immune system engages. Both innate and adaptive immunity depend on the ability of the immune system to distinguish between self and non-self molecules. In immunology, self-molecules are those components of an organism’s body that can be distinguished from foreign substances by the immune system. One class of non-self molecules, called antigens (short for antibody generators), are defined as substances that bind to specific immune receptors and elicit an immune response.

Immune response: The activation of any aspect of the immune system either by self or foreign material.

Immunity: The condition of being immune; the protection against infectious disease conferred either by the immune response generated by immunization or previous infection or by other non-immunologic factors.

Immunofixation: A laboratory test used to determine the presence and type of monoclonal immunoglobulins found in the serum or urine.

Immunoglobulins (Igs): Any of the structurally related molecules formed by B-cells as antibodies; immunoglobulins are divided into five basic classes or isotypes (immunoglobulin M, immunoglobulin G, immunoglobulin A, immunoglobulin E, and immunoglobulin D with their related subclasses) on the basis of structure and biologic activity.

Immunoglobulin M (IgM): A specific immunoglobulin, an excess of which characterizes Waldenstrom’s macroglobulinemia. Immunoglobulin M is a basic antibody that is produced by B-cells. Immunoglobulin M is, by far, physically the largest antibody in the human circulatory system. It is the first antibody to appear in response to initial exposure to antigen. Immunoglobulin M antibodies appear early in the course of an infection and usually reappear, to a lesser extent, after further exposure. This biological property of immunoglobulin M makes it useful in the diagnosis of infectious diseases. Demonstrating immunoglobulin M antibodies in a patient’s serum indicates recent infection.

Immunomodulatory drugs (IMIDs): A class of drugs that constitute thalidomide, lenalidomide and pomalidomide, used in the treatment of multiple myeloma and, less commonly, Waldenstrom’s macroglobulinemia. Immunomodulatory drugs are not traditional chemotherapy drugs; their mechanism of action is not completely understood, but they are antiangiogenic and help stimulate T-cell and natural killer cell production.

Immunosuppression: An extreme weakening of the immune response caused by drugs or other means. Immunosuppression involves an act that reduces the activation or efficacy of the immune system. Some portions of the immune system itself have immunosuppressive effects on other parts of the immune system, and immunosuppression may occur as an adverse reaction to treatment for other conditions.

Immunotherapy: Treatment to boost or restore the ability of the immune system to fight cancer, infections, and other diseases; also used to lessen certain side effects that may be caused by some cancer treatments. Agents used in immunotherapy include monoclonal antibodies, growth factors, and vaccines. These agents may also have a direct antitumor effect.

IMO-8400: An oral drug that targets the Toll-like receptors 7, 8, and 9. It is being tested in patients with Waldenstrom’s macroglobulinemia.

Indolent: Slow growing.

Inflammation: A localized protective response elicited by injury or destruction of tissues, which serves to destroy, dilute, or wall off (sequester) both the injurious agent and the injured tissue. It is characterized in the acute form by the classical signs of pain (dolor), heat (calor), redness (rubor), swelling (tumor), and loss of function. Histologically, it involves a complex series of events, including dilatation of arterioles, capillaries, and venules, with increased permeability and blood flow; exudation of fluids, including plasma proteins; and leukocytic migration into the inflammatory focus.

Infusion: The introduction of a fluid into a vein.

Injection: Use of a syringe and needle to push fluids or drugs into the body; often called a “shot.”

Intravenous (IV): Into the vein.

Intravenous immunoglobulin G (IVIg): Intravenous immunoglobulin is a blood product administered into the vein. It contains the pooled, polyvalent immunoglobulin G extracted from the plasma of over one thousand blood donors. Intravenous immunoglobulin G’s effects last between 2 weeks and 3 months.

Lactate dehydrogenase (LDH): Lactate dehydrogenase is an enzyme present in the cytoplasm of all cells. Measurement of total lactate dehydrogenase activity is used to screen liver, muscle, and myocardial disease. Lactate dehydrogenase is often used as well as a marker for certain leukemias, lymphomas, anemia, and multiple myeloma. Lactate dehydrogenase isoenzymes can be fractionated to determine the predominant source of lactate dehydrogenase. Isoenzymes are noted in the heart muscle and red blood cells (LD₁); concentrated in white blood cells (LD₂); highest in the lungs and platelets (LD₃); highest in the kidney, placenta, and pancreas (LD₄); highest in the liver and skeletal muscle (LD₅).

Lenalidomide (Revlimid): A drug that is similar to thalidomide and is used to treat multiple myeloma and other types of cancer.

Leukocytes: White blood cells formed in the bone marrow, including lymphocytes, neutrophils, eosinophils, monocytes/macrophages, basophils, and natural killer cells.

Leukopenia: An abnormally low number of white blood cells.

Light chain: A light chain is the small polypeptide subunit of a protein complex.

Kappa and lambda light chains: There are only two types of light chains found in the basic four-chain immunoglobulin molecule. Kappa light chains, encoded by the immunoglobulin kappa locus on chromosome 2, and lambda light chains, encoded by the immunoglobulin lambda locus on chromosome 22. Both types of light chains are present in all individuals, and either of the kappa or lambda light chain types may combine with any of the heavy chain types, but in any one type of B-cell immunoglobulin molecule both light chains and heavy chains are of the same type. In a healthy individual, the total kappa to lambda ratio is roughly 2:1 in serum (measuring intact whole antibodies) or 1:1.5 if measuring free light chains, with a highly divergent ratio indicative of neoplasm.

Lymph nodes: Part of the immune system’s lymphatic system, these are bean-shaped organs found in the underarms, groin, neck, and abdomen that act as filters for the lymph fluid as it passes through them. The lymph nodes are major sites of antigen trapping by lymphocytes, which in turn activate an immune response.

Lymphadenopathy: Enlargement of the lymph nodes.

Lymphoma: Cancer of the lymphatic system, which includes the bone marrow, spleen, thymus, lymph nodes, and vessels that carry fluid and infection-fighting cells, or any neoplastic disorder of the lymphoid tissue. The lymphomas are classified generally in two subsets. These are Hodgkin’s lymphoma and the non-Hodgkin’s lymphomas, which are then subsequently classified as low grade (includes Waldenstrom’s macroglobulinemia), intermediate grade, and high grade (includes diffuse large B-cell lymphoma).

Lymphoplasmacytic lymphoma (LPL): A modern term for Waldenstrom’s macroglobulinemia under the REAL classification system (Revised European-American Classification of Lymphoid Neoplasms).  It refers to the morphology of the cells which are intermediate in appearance between lymphocytes and plasma cells.  Other classification systems refer to Waldenstrom’s macroglobulinemia as a subset of lymphoplasmacytic lymphoma which specifically secretes monoclonal IgM immunoglobulin.

M-spike: Also called monoclonal spike, monoclonal protein, or monoclonal immunoglobulin. An IgM M-spike is so characteristic of Waldenstrom’s macroglobulinemia that it can be used for both diagnosis of disease and follow-up of patients. This monoclonal immunoglobulin can be detected using serum protein electrophoresis which separates the blood proteins into groups based on charge and size. There’s a predictable pattern of proteins in normal serum with each protein migrating to a certain point on an electrophoretic gel plate. Immunoglobulins migrate to a unique place called the gamma region, and because they are all different (in normal patients), they migrate to slightly different places within that region, giving a gentle bell-shaped curve or smear (depending on whether you’re looking at a tracing or the actual bands on the gel). In Waldenstrom’s macroglobulinemia, the immunoglobulin is monoclonal, so that all of it migrates to exactly the same spot on the gel. This results in a big spike (if you’re looking at a tracing) or a very distinct, crisp, strong band (if you’re looking at the gel itself).

Macrophage: A type of white blood cell that interacts with antigens and presents these antigens to T-cells, thus activating the T-cells. Macrophages that circulate in the blood are called monocytes, whereas those that reside in certain tissues are called tissue macrophages, or macrophages proper. Macrophages are capable of phagocytosis, and they secrete various substances that enhance the immune response to infectious agents and malignant cells. (See Antigen-presenting cells.)

Magnetic resonance imaging (MRI): Magnetic resonance imaging, also known as nuclear magnetic resonance imaging or magnetic resonance tomography, is a medical imaging technique used in radiology to visualize detailed internal structures. Images are produced by passing the patient through a tubular structure that generates a powerful electromagnetic field.  The hydrogen ions in the body are subjected to a high-intensity radiofrequency magnetic field and respond by emitting a radiofrequency signal that is then processed by computer to produce an image on film or computer.

Maintenance rituximab (Rituxan): A series of regular infusions of rituximab given over a period of time (usually two years) in an effort to prolong the response a patient has had to a previous therapy containing rituximab.

Minor response: In Waldenstrom’s macroglobulinemia, a minor response following treatment is characterized by a detectable monoclonal IgM protein, a reduction in serum IgM level of equal to or greater than 25% but less than 50% from baseline, and no new signs or symptoms of active disease.

Monoclonal antibodies (MABs): Laboratory-produced identical antibodies that can target a specific antigen.

Monoclonal antibody therapy: The use of laboratory-developed antibodies that can locate and bind to antigens in the body, including tumor cells.  Each monoclonal antibody is made to bind one specific antigen.  They can be used alone or to carry drugs, toxins, or radioactive materials directly to a tumor.

Monoclonal gammopathy of undetermined significance (MGUS): Formerly known as benign monoclonal gammopathy.  A benign condition in which a paraprotein (immunoglobulin or immunoglobulin light chain that is produced in excess) is found in the blood during standard laboratory tests. It resembles multiple myeloma and similar diseases, but the levels of antibody are lower. It produces no symptoms or problems, and no treatment is indicated.  Patients with MGUS are at increased risk of developing certain cancers, including multiple myeloma and Waldenstrom’s macroglobulinemia.

Monocytes: A type of white blood cell that is mobile and present in the circulation, comprises 2-5% of the circulating white blood cells, and breaks down old blood cells and microorganisms.

Monotherapy: Treatment of a condition by means of a single drug or modality.

Mucositis: A complication of some cancer therapies in which the lining of the digestive system becomes inflamed; often seen as sores in the mouth.

Multiple myeloma (MM): Multiple myeloma, also known as plasma cell myeloma or Kahler’s disease (after Otto Kahler), is a cancer of plasma cells, a type of white blood cell normally responsible for producing antibodies. In multiple myeloma, collections of abnormal plasma cells accumulate in the bone marrow, where they interfere with the production of normal blood cells. Most cases of myeloma also feature the production of a paraprotein, an abnormal antibody which can cause kidney problems. Bone lesions and hypercalcemia (high calcium levels) are also often encountered.

Mutation: Any change in the DNA of a cell.

MYD88: A gene called myeloid differentiation primary response gene 88 that codes for the MYD88 protein, which plays a central role in the innate and adaptive immune response. This protein is an essential one in the interleukin-1 and Toll-like receptor signaling pathways.

MYD88 L265P: A mutation in the MYD88 gene that changes the amino acid leucine to proline at amino acid position 265. This mutation is found in at least 90% of Waldenstrom’s macroglobulinemia patients and is important to the continued growth and proliferation of WM cells because of its action on the NF kappa B pathway.

Myelodysplasia: Production of abnormal blood cells in the bone marrow that can lead to leukemia.

Myelodysplastic syndrome (MDS): (formerly known as pre-leukemia) A diverse collection of hematological medical conditions that involve ineffective production or abnormality (dysplasia) of the myeloid class of blood cells.  Patients with MDS often develop severe anemia and require frequent blood transfusions. MDS can occur as the result of mutations induced by previous therapies, such as chemotherapy or radiation, given for a pre-existing condition.

Myelosuppression: A condition in which bone marrow activity is decreased, resulting in decreased platelets and red and white blood cells.  Myelosuppression can be a side effect of some cancer treatments.

Natural killer (NK) cell): A type of white blood cell, comprising 3-5% of peripheral leukocytes, which has

Neutropenia: A lower-than-normal level of neutrophils, a type of white blood cells.

Neutrophils: Also known as polynuclear neutrophils or polymorphonuclear neutrophils, these are multinucleate types of white blood cells that have more than one nucleus per cell with one common cytoplasm. Normally, neutrophils contain a nucleus divided into 3 – 5 lobes connected by slender threads of DNA material. Neutrophil granulocytes are the most abundant type of white blood cells in mammals and form an essential part of the innate immune system. In general, they are subdivided into segmented neutrophils (or segs) and banded neutrophils (or bands). They form part of the polymorphonuclear cell family together with basophils and eosinophils.

NF kappa B: A protein complex that controls transcription of DNA and plays a key role in regulating the immune response to infection. Incorrect regulation of NF kappa B has been linked to cancer, inflammatory, and autoimmune diseases. It plays an important role in the growth and proliferation of Waldenstrom’s macroglobulinemia cells.

Night sweats: Sleep hyperhidrosis, more commonly known as the night sweats, is the occurrence of excessive sweating during sleep. The sufferer may or may not also suffer from excessive perspiration while awake.

Non-Hodgkin’s lymphoma (NHL): The non-Hodgkin lymphomas are a diverse group of blood cancers that include any kind of lymphoma except Hodgkin’s lymphomas.  Non-Hodgkin lymphomas can occur at any age and are often marked by lymph nodes that are larger than normal, fever, and weight loss. These various types can be divided into aggressive (fast-growing), intermediate, and indolent (slow-growing) and can originate from either B-cells or T-cells.

Nucleoside analog: Part of a larger class of anti-cancer drugs termed antimetabolites, which act specifically on proliferating cells.  Fludarabine (Fludara) and cladribine (2CdA or Leustatin) are two purine analogs commonly used in treating WM.

Obinutuzumab (Gazyva): A humanized monoclonal antibody that has been approved for the treatment of chronic lymphocytic leukemia and is being tested in patients with Waldenstrom’s macroglobulinemia. It targets the same CD20 protein on B-cells as rituximab.

Ofatumumab (Arzerra / HuMax-CD20): A drug used to treat chronic lymphocytic leukemia (CLL) that has not gotten better with other chemotherapy. It is also being studied in the treatment of other types of cancer, including non-Hodgkin’s lymphoma and Waldenstrom’s macroglobulinemia. Ofatumumab binds to CD20, a protein on the surface of normal B-cells and most B-cell tumors. It is a type of monoclonal antibody.

Overall survival: The percentage of people in a study or treatment group who are still alive for a certain period of time after they were diagnosed with or started treatment for a disease, such as cancer.

Paraprotein: An abnormal plasma protein, such as the monoclonal IgM of Waldenstrom’s macroglobulinemia.

Partial response (PR): (Also see Response). In Waldenstrom’s macroglobulinemia, a partial response to treatment is characterized by a detectable monoclonal IgM, a reduction in serum IgM equal to or greater than 50% but less than 90% from baseline, a reduction in the size of enlarged lymph nodes and enlarged spleen if present at baseline, and no new symptoms or signs of active disease.

Peripheral neuropathy (PN): A clinical symptom where there is a permanent or transient problem with the functioning of the nerves outside the spinal cord. The symptoms of a neuropathy may include numbness, weakness, tingling, burning pain, and loss of reflexes (usually in hands and / or feet). The pain may be mild or severe and disabling.

Petechiae: Pinpoint, unraised, round red spots under the skin caused by bleeding.

Plasma: The fluid component of blood containing water, electrolytes, and various proteins.

Plasma cells: Terminally differentiated white blood cells of the B-cell lineage that produce antibodies. In multiple myeloma, the plasma cell becomes malignant and produces in most cases large amounts of IgG antibodies

Plasmapheresis (PP): The process of removing a donor’s plasma to extract a specific component (monoclonal immunoglobulin M in the case of Waldenstrom’s macroglobulinemia patients) and returning the remaining plasma to the donor. The process uses continuous circulation of blood from a donor through an apparatus and back to the donor. This process makes it possible to remove specific substances from large volumes of plasma. Hemapheresis or apheresis is a similar procedure whereby platelets, red cells, white cells, stem cells or plasma constituents can be removed separately.

Platelets (thrombocytes): Cells formed in the bone marrow from hematopoietic stem cells; they circulate in the blood and are necessary to help the blood clot and control bleeding.

Polyclonal: Derived from different cells. Normal immunoglobulin M is polyclonal since it is derived from many different B-cells each producing a distinct unique immunoglobulin M as opposed to monoclonal immunoglobulin M produced by the Waldenstrom’s macroglobulinemia malignant clone.

Polymerase chain reaction (PCR): A laboratory method using the enzyme polymerase (which catalyzes polymerization forming compounds of high molecular weight) to make many copies of a specific DNA sequence.

Positron emission tomography (PET): Commonly called a PET scan, this is a unique type of imaging test that produces a three-dimensional image or picture of functional processes in the body, helping doctors see how the organs and tissues inside your body are actually functioning.

Prognosis: A prediction of the course of the disease and its outcome.

Progression-free survival: The length of time during and after the treatment of a disease, such as cancer, that a patient lives with the disease but it does not get worse. In a clinical trial, measuring the progression-free survival is one way to see how well a new treatment works.

Proteasome inhibitor:  A drug that blocks the action of proteasomes. A proteasome is a large protein complex that helps destroy other cellular proteins when they are no longer needed. When the action of the proteasome is blocked, this cellular protein “garbage” backs up in the cell and eventually kills it. Proteasome inhibitors are used in the treatment of multiple myeloma and Waldenstrom’s macroglobulinemia.

Proteomics: The study of the structure and function of proteins, including the way they work and interact with each other inside cells.

Protocol: A detailed plan of a medical experiment, treatment, or procedure.  In clinical trials, it states what the study will do, how it will be done, and why it is being done. It explains how many people will be in the study, who is eligible to take part in it, what study drugs or other interventions will be given, what tests will be done and how often, and what information will be collected.

Pyrexia: A fever.

R-CHOP: An abbreviation for a chemoimmunotherapy combination that is used to treat non-Hodgkin’s lymphoma and mantle cell lymphoma and is being studied in the treatment of other types of cancer. It includes the drugs rituximab, Cytoxan, hydroxydoxorubicin (also known as Doxorubicin or Adriamycin), Oncovin (vincristine), and prednisone.

Reference ranges: In medicine, a set of values that a doctor uses to interpret a patient’s test results. The reference range for a given test is based on test results for 95% of the healthy population. Sometimes patients whose test results are outside of the reference values may be healthy, and some patients whose test results are within the reference values may have a health problem. The reference range for a test may be different for different groups of people (for example, men and women).

Refractory: Not responding to treatment.

Regimen: A treatment plan that specifies the dosage, the schedule, and the duration of treatment.

Relapse: The return of disease after it has been treated and the patient has been in remission.

Resistance: In the context of cancer, resistance is the ability of cancer cells to circumvent the effects of drug therapy so that the drug does not work well and the cancer cells grow.

Response: A description of how cancer has responded to treatment.

Rituximab (Rituxan): A drug used to treat certain types of B-cell non-Hodgkin’s lymphoma. It is also used with other drugs to treat chronic lymphocytic leukemia and rheumatoid arthritis. It is being studied in the treatment of other types of cancer and other conditions. Rituximab binds to a protein called CD20, which is found on B-cells, and it kills cancer cells by utilizing the patient’s own immune system. It is a type of monoclonal antibody.

Salvage therapy: Any therapy administered after first-line treatment has failed.

Serum: The fluid component of clotted blood.

Serum protein electrophoresis (SPEP): A laboratory test that examines specific proteins in the blood called globulins by exposing the collected serum to an electric current to separate the serum protein components into five classifications by size and electrical charge (serum albumin, alpha-1 globulins, alpha-2 globulins, beta globulins, and gamma globulins). In Waldenstrom’s macroglobulinemia and related disorders, this technique is used to measure immunoglobulin proteins such as IgM, IgG, and IgA.

Serum viscosity (SV): The physical property of serum as it relates to its “thickness”. The serum viscosity is affected by the concentration of constituents in the serum. The greater the number of soluble molecules in the serum, the higher will be the viscosity.

Shingles: The disease caused when varicella zoster virus is reactivated later in life in a person who has had chickenpox.

Smoldering Waldenstrom’s macroglobulinemia: Not yet full-blown Waldenstrom’s macroglobulinemia. Smoldering Waldenstrom’s macroglobulinemia is defined clinically as having a serum monoclonal immunoglobulin M protein equal to or greater than 3 g/dL and/or bone marrow lymphoplasmacytic infiltration equal to or greater than 10%, but with no evidence of end-organ damage (anemia, constitutional symptoms, hyperviscosity, lymphadenopathy (swollen/enlarged lymph nodes), or hepatosplenomegaly).

Spleen: The largest structure in the lymphoid system, the spleen is a gland-like organ situated in the left upper abdomen. It serves as a reservoir of blood, produces lymphocytes and plasma cells, and functions as a “filter” for the blood by removing damaged red blood cells from the circulation.

Splenectomy: Surgical removal of the spleen.

Stem cell mobilization: The process of using certain drugs to increase the movement of stem cells from the bone marrow into the peripheral blood so that they can be collected for a stem cell transplant.

Stem cell transplant (SCT): A stem cell transplant is the infusion of healthy stem cells into the body. A stem cell transplant may be necessary if the bone marrow stops working and doesn’t produce enough healthy stem cells. A stem cell transplant can help the body make enough healthy white blood cells, red blood cells or platelets, and reduce the risk of life-threatening infections, anemia and bleeding.

Subcutaneous: Under the skin.

Symptom(s): Subjective evidence of a disease, usually observed by the patient.

T (thymus-derived)-cells / T-lymphocytes / T-cells: T-cells are probably the most complex cells of the immune system, given the diversity of T-cell types, the wide range of cytokines, growth factors and immune modulators produced by activated T-cells, the complexity of T-cell interaction with antigens, and the complexity of T-cell maturation in the thymus. In general, they are white blood cells that mature in the thymus and attack viruses.

Targeted therapy: A type of treatment that uses drugs or other substances, such as monoclonal antibodies, to identify and attack specific cancer cells. Targeted therapy may have fewer side effects than other types of cancer treatments.

Thalidomide (Thalomid): A drug that is used to treat multiple myeloma in patients who have just been diagnosed and to treat a painful skin disease related to leprosy. It is also being studied in the treatment of other types of cancer. Thalidomide is an angiogenesis inhibitor as well as belonging to a class of agents called immunomodulatory drugs (IMIDs).

Thrombocytopenia: An abnormally low number of platelets in the blood.

Toxicity: Having to do with poison or something harmful to the body. Toxic substances usually cause unwanted side effects.

Ultrasound (ultrasonography): A diagnostic method that generates images based on the differences in the ability of tissues of various densities to slow ultrasound waves.

Very good partial response: In Waldenstrom’s macroglobulinemia, a very good partial response following treatment is characterized by a detectable monoclonal IgM protein, a reduction in serum IgM level equal to or greater than 90% from baseline, complete resolution of enlarged lymph nodes and enlarged spleen if present at baseline, and no new signs or symptoms of active disease.

Viscosity: The resistance to the flow of a fluid, e.g. the thickness of the blood, or the ease with which it flows in the circulation.

Waldenstrom’s macroglobulinemia (WM): Waldenstrom’s macroglobulinemia is a rare, indolent non-Hodgkin’s lymphoma that begins in white blood cells called B-lymphocytes or B-cells. These B-cells mature in the lymph nodes, spleen, bone marrow, and other tissues. Lymphoplasmacytic cells are cells that are in the process of maturing from B-cells to plasma cells. In Waldenstrom’s macroglobulinemia, abnormal lymphoplasmacytic cells multiply out of control, producing large amounts of a protein called monoclonal immunoglobulin M (also known as “macroglobulin”). High levels of immunoglobulin M in the blood cause hyperviscosity (blood thickness), which leads to many of the symptoms of Waldenstrom’s macroglobulinemia.

Watch and wait (W&W): Watch and wait (or watchful waiting) is often used with indolent or incurable cancers and means that a doctor does not actively treat a patient, but rather monitors the disease. This is desirable because treating asymptomatic patients does not cure the disease, improve quality of life, or change the outcome, plus many treatments have adverse side effects. The watch and wait method is used to ensure that treatment is begun when it is necessary to alleviate symptoms and improve quality of life. During this time, the patient will undergo regular medical testing to determine the current status of his or her disease.