Issuu

Myeloma-related terms from A to Z A

Acute: In reference to disease, of sudden onset or of short duration, rapidly progressive, and in need of immediate care.

Acute tubular necrosis (ATN): Damage to or destruction of cells that form the renal (kidney) tubules, tiny ducts that help filter the blood when it passes through the kidneys. ATN can lead to acute renal failure. It may be possible to recover kidney function if not all of the tubular cells are affected.

Administration-related reaction (ARR): Reaction to treatment administered as an intravenous (IV) infusion or a subcutaneous (SQ) injection. See Infusion-related reaction (IRR) and Cytokine.

Adrenal glands: Glands located at the top of the kidneys that are chiefly responsible for releasing sex hormones and cortisol, a hormone that helps human beings respond to stress.

Adverse event (AE): See Side effect .

Aiolos: An Ikaros family protein. See Ikaros.

Albumin (ALB): A protein found in the blood (serum). The serum ALB (sALB) test measures this normal protein in the blood. Production of ALB is inhibited when myeloma is very active.

Albuminuria: The presence of an excess of serum albumin in the urine.

Alkylating agent: A chemotherapy agent that blocks cell division. Alkylating agents were the earliest effective drugs used in the treatment of myeloma. Melphalan and cyclophosphamide are examples of alkylating agents currently used to treat myeloma.

Allergen: A substance that causes an allergic reaction.

Allergenics: Licensed and regulated products used for diagnosis or treatment of allergic diseases, or to determine the cause of allergic diseases.

Allogeneic transplant: See Transplant (transplantation).

Amyloid light-chain (AL) amyloidosis: AL amyloidosis is a plasma cell disorder in which light chain proteins are not excreted by the kidneys, but become crosslinked with each other, and these amyloid fibrils are then deposited in tissues and organs. See Amyloidosis.

Amyloidosis: A group of systemic diseases characterized by the deposition of amyloid protein in various organs or tissues. AL amyloidosis is the one type of amyloidosis that is related to myeloma. See Amyloid light-chain (AL) amyloidosis.

Analgesic: Any drug that relieves pain. Aspirin and acetaminophen are mild analgesics.

Analog: A chemical compound that is structurally similar to another but differs slightly in composition.

Anemia: Red blood cells contain hemoglobin, a protein that carries oxygen to the body’s tissues and organs. Anemia is usually defined as a decrease in hemoglobin < 10 g/dL or as a decrease of ≥ 2 g/dL from the normal level for an individual. Low levels of oxygen in the body may cause shortness of breath and feelings of exhaustion. Many newly diagnosed myeloma patients have anemia.

Anesthesia: Loss of feeling or awareness. Local anesthesia causes loss of feeling in a part of the body. General anesthesia induces loss of sensation in the entire body that can cause loss of consciousness.

Angiogenesis: Blood vessel formation, which usually accompanies the growth of malignant tissue, including myeloma.

Angiogenesis inhibitors: Compounds that reduce new blood vessel formation associated with cancer cell growth.

Ankylosing spondylitis: A form of chronic inflammation of the spine and the sacroiliac joints.

Antibiotics: Drugs used to treat bacterial infections.

Antibody: A protein produced by plasma cells in response to an antigen that enters the body. See Immunoglobulin (Ig).

Antibody-drug conjugate (ADC): An anti-cancer therapy that links a Monoclonal antibody directed at cancer cells with a drug that is toxic to cancer cells.

Anti-emetic agent: A drug that prevents or controls nausea and vomiting.

Antifungal agent: A drug used to treat fungal infections.

Antigen: Any foreign substance that causes the immune system to produce natural antibodies. Examples of antigens include bacteria, viruses, parasites, fungi, and toxins.

Antihistamine: A drug that acts against histamine, a powerful and highly irritant agent released in the body after contact with certain allergens.

Anti-inflammatory: A substance or treatment that reduces inflammation or swelling.

Antineoplastic agent: A drug that prevents, kills, or blocks the growth and spread of cancer cells. See Neoplasm.

Anti-oncogene: A gene that makes a protein called a tumor suppressor gene, which protects a cell on the path to cancer. See Oncogene and Tumor suppressor gene.

Apheresis: A procedure that uses a machine to separate whole blood so that one specific component can be collected while other components are immediately re-infused back into the bloodstream of the patient or donor.

Appendicular skeleton: The part of the skeleton consisting of the appendages: the bones of the arms and legs.

Apoptosis: A normal cellular process leading to the death of a cell.

Arrhythmia: An arrhythmia is a problem with the rate or rhythm of the heartbeat. It means that the heart beats too quickly, too slowly, or with an irregular pattern. Arrhythmias are caused by problems with the heart’s electrical conduction system.

Aspiration: The process of removing fluid or tissue, or both, from a specific area such as the bone marrow.

Asthenia: A condition in which the body lacks or has lost strength either as a whole or in any of its parts.

Asymptomatic: Producing or showing no signs or symptoms.

Atherosclerosis: The deposits of fats, cholesterol, and other substances inside the artery walls.

Autoantibody: An antibody produced by an individual’s immune system in response to one or more of that individual’s own proteins. Autoantibodies can target a person’s own tissues and/or organs, and may cause autoimmune disorders such as lupus, rheumatoid arthritis, Type 1 diabetes, and others. See Antibody.

Autocrine: In myeloma, autocrine signaling is how the cancer cells produce growth factors that bind to their own receptors, thereby promoting survival, growth, and drug resistance of malignant cells. Also see Paracrine.

Autoimmune disease: A condition that occurs when the immune system abnormally creates antibodies to a normal body part. Common autoimmune diseases include Type 1 diabetes, celiac disease, inflammatory bowel disease, multiple sclerosis, psoriasis, and rheumatoid arthritis.

Autologous transplant: See Transplant (transplantation).

Autonomic nervous system: The part of the nervous system that regulates functions of organs over which we have no conscious control. The autonomic nerves connect the spinal cord to the internal organs, including the blood vessels, stomach, intestines, lungs, liver, kidneys, bladder, and heart.

Axial skeleton: Consists of spine, pelvis, ribs, and skull. The axial skeleton is most commonly affected by myeloma, along with the upper ends of the long bones of the arms and legs.

B

B-cell maturation antigen (BCMA): A protein involved in myeloma cell growth and survival. BCMA is found on the surface of cells in all patients with myeloma.

B cells (B lymphocytes): B cells are white blood cells that originate and mature in the bone marrow. When activated by a specific antigen, some B cells develop into plasma cells and make antibodies to that specific antigen.

Bacteria: Single-celled microorganisms that can exist either as independent (free-living) organisms or as parasites (dependent on another organism for life). The plural of bacterium.

Baseline: The initial known data that is gathered and used for comparison with later data.

Basophil: A type of white blood cell. Basophils help prevent blood from clotting and release histamine, a signaling compound, during allergic reactions.

Bence-Jones myeloma: Myeloma characterized by the presence of Bence-Jones protein, an abnormal protein in urine made up of free kappa or lambda light chains. See Bence-Jones protein.

Bence-Jones protein: A monoclonal protein that is composed of either free kappa or free lambda light chains. Unlike myeloma protein heavy chains that are too large to be filtered through the kidneys, Bence-Jones light chains can be filtered through the kidneys and then pass into the urine. The presence of any Bence-Jones protein in the urine is abnormal. See Bence-Jones myeloma.

Benign: Not cancerous; does not invade nearby tissue or spread to other parts of the body.

Beta-2 microglobulin (β2-microglobulin, β2M, or β2M): A small protein found in the blood (serum) that is a tumor marker in myeloma. The serum β2M (sβ2M) test is used to detect levels in the blood. In addition to myeloma, other factors (e.g., viral infection) can raise sβ2M levels.

Biologics: Products that are composed of living organisms or contain components of living organisms. Biological products include vaccines, blood and blood components, cells, genes, tissues, allergenics, and recombinant therapeutic proteins. Biologics are used to treat numerous diseases and conditions. Also see Biosimilars.

Biomarker: A measurable molecule found in body fluids or tissues that can provide information about a process, condition, or disease. In myeloma, biomarkers are used to help choose the most appropriate treatment as well as to assess response treatment. Also called Tumor marker.

Biopsy: The collection of tissue for microscopic examination to aid in diagnosis.

Biosimilars: Products with a molecular structure that is similar to – but not an exact match with – the reference product. Biosimilars have no clinically meaningful difference in safety, purity, and potency. Also see Biologics.

Bispecific antibody: An artificial antibody that binds to two (bi) targeted cells.

Bisphosphonate: A type of drug that protects against osteoclast activity (bone breakdown) and binds to the surface of bone where it is being resorbed or destroyed.

Blood cell: A structure in the bone marrow that typically includes red blood cells, white blood cells, and platelets.

Blood count: The number of red blood cells, white blood cells, and platelets in a sample of blood.

Blood glucose: A type of blood sugar that the body produces from the food in our diet. Glucose is transported via the bloodstream to all the cells in our body. It is our primary source of energy. Certain medications can affect our blood glucose levels. There are tests that measure and monitor blood glucose.

Blood stem cells: Stems cells in the bone marrow that are responsible for making all the blood cells. The medical term is hematopoietic stem cells.

Blood urea nitrogen (BUN): A measure of the urea level in the blood.

Urea is excreted by the kidneys. BUN is a laboratory blood test to assess kidney function. Diseases such as myeloma, which can compromise kidney function, frequently lead to increased levels of BUN in the bloodstream.

Bone marrow: The soft, spongy tissue in the center of bones that produces white blood cells, red blood cells, and platelets. When myeloma is growing, myeloma cells build up in the bone marrow.

Bone marrow aspiration: The removal, by a needle, of a sample of fluid and cells from the bone marrow for examination under a microscope.

Bone marrow biopsy: The removal, by a hollow-bore needle, of a sample of tissue from the bone. Bone marrow biopsy is usually done at the same time as bone marrow aspiration.

Bone marrow failure: When the bone marrow is unable to produce enough healthy blood cells. Bone marrow failure can be acquired or inherited. It can be fatal if left untreated.

Bone marrow transplant: See Transplant (transplantation).

Bone-modifying agent (BMA): A class of drugs used to prevent or treat bone breakdown. In myeloma, BMAs include Xgeva® (denosumab), Zometa® (zoledronic acid), and Aredia® (pamidronate).

Bone remodeling: The normal balance of bone production and maintenance between osteoclast cells (that break down and remove old bone) and osteoblast cells (that create new bone matrix).

CC-reactive protein (CRP): A protein made in the liver that increases in amount when there is inflammation in the body.

Calcium: A mineral found mainly in the hard part of bone matrix (hydroxyapatite). If produced or released in excess, it can build up in the bloodstream. See Hypercalcemia.

Cancellous bone: Also known as trabecular bone; the light, porous bone enclosing numerous large spaces that give it a sponge-like appearance. Trabecular bone contains marrow and blood vessels.

Cancer: A term for diseases in which malignant cells divide without control. Cancer cells can invade nearby tissues and spread through the bloodstream and lymphatic system to other parts of the body.

Carcinogen: Any substance or agent that produces or stimulates cancer growth.

Catheter: A tube that is placed in a blood vessel to provide a pathway for drugs or nutrients. A central venous catheter (CVC) is special tubing that is surgically inserted into a large vein near the heart and exits from the chest or abdomen. The catheter allows medications, fluids, or blood products to be given and blood samples to be taken.

CD34+: Cluster of differentiation (CD) 34 is a cell surface protein on hematopoietic stem cells. It is used to select and quantify the stem cells required to safely support a transplant procedure.

Cell: The basic unit of any living organism. Millions of microscopic cells comprise each organ and tissue in the body.

Cell differentiation: The process during which young, immature (unspecialized) cells develop individual characteristics and reach their mature (specialized) form and function.

Cell proliferation: An increase in the number of cells as a result of cell growth and cell division.

Central nervous system (CNS): The part of the nervous system consisting of the brain and spinal cord. The CNS is made up of nerve cells and groups of nerves that transmit messages between the brain and the rest of the body.

Cereblon: A protein that is encoded by the CRBN gene, which is found on the short arm of human chromosome 3.

Cereblon E3 ligase modulatory drug (CELMoD): This new drug class in myeloma is being studied in clinical trials (e.g., iberdomide, mezigdomide). By binding to cereblon, CELMoDs are able to overcome drug resistance to immunomodulatory agents while also engaging other elements of the immune system to target and kill myeloma cells.

Checkpoint inhibitor: A safety mechanism built into our immune system to help keep immune responses in check. Checkpoint inhibitors that block programmed cell death protein 1 (PD-1) reduce the deactivation of T cells and enhance the ability of T cells to kill cancer cells.

Chemokine: A type of protein within the cytokine family that induces cell migration. See Cytokine.

Chemotherapy: The use of drugs to kill cancer cells. Combination chemotherapy uses more than one drug in a cancer treatment regimen.

Chimeric antigen receptor (CAR) T-cell therapy: In myeloma, this immunotherapy involves collecting the patient’s T cells, engineering them in a laboratory, and multiplying the engineered T cells for re-infusion into the patient to attack the patient’s own myeloma cells.

Chromatid: One of two identical chromosomal strands into which a chromosome splits before cell division.

Chromosomal abnormalities: See Chromosome.

Chromosome: A strand of DNA and proteins in the nucleus of a cell. Chromosomes contain genes and function in the transmission of genetic information. Normally, human cells contain 46 chromosomes (23 pairs).

• Chromosomal deletion – Genetic mutation in which part or all of a chromosome is lost during DNA replication. Chromosomal deletions that occur in myeloma include loss of the long arm of chromosome 13 (written as 13q–) or loss of the short arm of chromosome 17 (written as 17p–).

• Chromosomal translocation – Genetic mutation in which parts of different chromosomes are rearranged. Written with a lowercase t followed by the numbers of the chromosomes with translocated genetic material. Translocations that occur in myeloma include t(4;14), t(11;14), t(14;16), and t(14;20).

Chronic: Persisting over a long period of time.

Clinical: Involving direct observation or examination of a patient.

Clinical trial: A medical research study with people who volunteer to test scientific approaches to a new treatment or a new combination therapy. Each clinical trial is designed to find better ways to prevent, detect, diagnose, or treat cancer and to answer scientific questions.

• Accrual – The process of enrolling patients in a clinical trial, or the number of patients already enrolled or anticipated to be enrolled in a clinical trial.

• Arm – A treatment group in a randomized study, in which there are two or more arms.

• Cohort – A group of patients in the same study receiving the same treatment or placebo.

• Control group – The arm of a randomized clinical trial that receives the standard treatment or placebo.

• Double-blind – When neither the patient nor the investigator knows the arm of the trial to which the patient is randomized. The purpose is to eliminate any bias in the reporting of results.

• Endpoint – The goal of the study. A clinical trial endpoint may aim to measure toxicity, response rate, or survival.

• Experimental group – The arm of a randomized trial that gets the new treatment.

• Intention-to-treat (ITT) population – All study participants, regardless of whether they adhered to the intended treatment protocol, did not adhere to the protocol, completed the study, or did not complete the study. ITT provides an estimate of treatment effectiveness in a real-world scenario.

• Per-protocol (PP) population – Study participants who adhered to the intended treatment protocol and completed the study.

• Placebo – An inert (inactive) substance often used in clinical trials for comparison with an experimental drug. No clinical trial for cancer patients in the U.S. can ethically or legally randomize patients to receive a placebo alone when they require treatment. In the placebo arm of a cancer treatment trial, patients receive treatment with approved therapy plus a placebo.

• Randomized clinical trial – A study in which patients are randomly assigned to receive a particular treatment.

• Phase I clinical trial – A study to determine the maximum-tolerated dose (MTD) and safety profile of a new drug or a new combination of drugs. It may be the first testing of a new treatment in humans. Please note that in combination therapies, the individual elements may already have been well-tested in humans.

• Phase II clinical trial – A study designed to determine the efficacy and safety of a new therapy that has been tested in a phase I trial. Patients are usually required to have measurable disease that is refractory to any standard treatment. If the results of a phase II study are clearly much better than the standard treatment, then the treatment may be approved without being tested in a phase III study. If results from a phase II study are promising, the treatment may then be tested in a phase III study.

• Phase III clinical trial – A study that compares two or more treatments. The endpoint of a phase III study may be survival or progression-free survival (PFS). Phase III studies are usually randomized, so patients don’t choose which treatment they receive. Some phase III trials compare a new treatment that had good results in phase II study with a standard-of-care treatment; other phase III studies compare treatments that are already in common use.

• Phase IV clinical trial – Even after a drug has been approved by the U.S. Food and Drug Administration (FDA) for use in a particular indication, there may be need for additional studies. For example, safety surveillance is designed to detect any rare or long-term side effects over a larger patient population and longer time period than was possible during the phase I–III clinical trials.

Clonal: Identical cells produced from a single original cell. The presence of clonal cells tends to indicate cancer.

Colony-stimulating factor (CSF): Proteins that stimulate the development and growth of blood cells. CSF drugs are used to mobilize stem cells from the bone marrow into the bloodstream prior to a stem cell transplant, and CSFs may also be used after the transplant to hasten blood count recovery, or to treat low white cell count.

Complement proteins: A complex system of more than 30 proteins that work together to help eliminate infectious microorganisms.

Complete blood count (CBC): The CBC test is used to measure the three key blood cells: red blood cells (RBC), white blood cells (WBC), and platelets. The CBC test is used in the diagnosis and monitoring of myeloma.

Complete response: See Response or remission.

Computed axial tomography (CAT or CT): Creates three-dimensional images of structures inside the body. In myeloma, used when X-rays are negative or for more detailed scanning of specific areas. Especially useful for detection or detailed evaluation of small areas of bone damage or nerve pressure.

Conditioning regimen: A treatment given to a patient to destroy cancer cells prior to stem cell transplant. The most common conditioning regimen given to myeloma patients is 200 mg of melphalan per square meter of body mass.

Congestive heart failure: A condition that occurs when the heart’s pumping function is weakened, causing a series of events that result in the body retaining fluid and salt. If fluid builds up in the arms, legs, feet, ankles, lungs, or other organs, the body becomes congested.

Consolidation therapy: Treatment that may be given after an autologous stem cell transplant (ASCT) to further deepen the patient’s response to ASCT. Usually, the same drug regimen is used as for induction therapy.

Constipation: The medical definition of constipation is 3 or fewer bowel movements within 1 week. The stool may be hard, dry, and difficult to pass. You may also have stomach cramps and bloating. Not eating enough fiber, not drinking enough fluids, being less active, as well as taking certain medications can contribute to constipation.

CRAB criteria: An elevated level of Calcium in the blood, Renal (kidney) damage, Anemia or low hemoglobin, and Bone damage related to myeloma. CRAB criteria has evolved into the SLiM-CRAB criteria.

Creatinine: A chemical compound normally excreted by the kidneys into the urine. If the kidneys are damaged, the serum level of creatinine builds up. The serum creatinine test is used to measure kidney function.

Cycle: Cancer patients often receive treatment at regular intervals that can be measured in days or weeks, followed by a possible period of rest. A Cycle is the amount of time between the start of one round of therapy and the start of the next round of therapy.

Cyst: An accumulation of fluid or semi-solid material within a sac. A cyst can occur in any organ or tissue.

Cytogenetics (karyotyping): This laboratory test detects missing, rearranged, or extra chromosomes. This test does not measure your inherent genetics. It assesses the chromosomes in your plasma cells, providing important information about your myeloma and helping to determine if it should be classified as high-risk or not. See Chromosome.

Cytokine: A protein that circulates in the bloodstream, usually in response to infection. Cytokines can stimulate or inhibit the growth or activity in other cells.

Cytokine release syndrome (CRS): A potentially fatal, uncontrolled immune reaction in which cytokines become highly elevated and trigger an overwhelming immune system response. A cytokine storm can seriously damage body tissues and organs. See Cytokine.

Cytopenia: A condition in which there is a lower-than-normal number of red blood cells (anemia), white blood cells (leukopenia), or platelets (thrombocytopenia). Pancytopenia is a condition in which all of a person’s blood cell levels are low.

Cytoplasm: The jellylike material inside the membrane of a human cell, excluding the cell’s nucleus.

DDeep vein thrombosis (DVT): A condition that occurs when a blood clot (thrombus) forms in one or more of the deep veins in the body, usually in the legs. A blood clot from a DVT can break loose (embolize) and travel to the heart or lungs. An embolus is potentially life-threatening. DVT can occur without any symptoms, or it can cause leg pain or swelling.

Dehydration: Excessive loss of water from the body. Symptoms and signs include thirst, dry mouth, weakness or lightheadedness (particularly if worse on standing up), dark urine, and a decrease in urination. Heat exposure, prolonged vigorous exercise, kidney disease, vomiting or diarrhea, as well as certain medications may lead to dehydration.

Dendritic cell: Dendritic cells boost immune response by activating helper T cells and stimulating them to release cytokines. Dendritic cells are one type of antigen-presenting cells (APC) that show antigens on their surface to other immune system cells for recognition and destruction, affecting long-term disease control and treatment outcome.

Deoxyribonucleic acid (DNA): The substance of heredity; a large molecule that carries the genetic information that cells need to replicate and to produce all components of the body.

Depth of response (DpR): In myeloma, research studies have demonstrated DpR to be a predictor of statistically superior outcomes, including prolonged progression‐free survival (PFS) and overall survival (OS) in patients achieving at least a very good partial response (VGPR) during treatment.

Diagnosis: The process of identifying a disease by its signs, symptoms, and test results.

Dialysis: The process of removing water, excess salt, and toxins from the blood when a person’s kidneys are no longer capable of doing so. The two types of dialysis are hemodialysis, which uses a machine, and peritoneal dialysis, which uses the lining of the abdomen (the peritoneum), to filter the blood.

Diarrhea: Diarrhea is defined as 3 or more loose stools per day. Severe diarrhea is defined as 7 or more loose stools per day requiring treatment with intravenous (IV) fluids or hospitalization.

Disease progression: See Progressive disease.

Disease stabilization: When cancer stops growing and remains stable.

Dose-limiting toxicity (DLT): When the side effects of the treatment are severe enough to prevent giving more of the same treatment.

Down-regulation: The process by which the quantity of a cellular component, such as RNA or protein, is decreased in a cell in response to an external variable.

Drug class: A group of medications that have a similar chemical structure or a similar Mechanism of action (MoA).

Drug resistance: When a drug becomes less effective and the patient’s cancer cells become more resistant to therapy.

Dual-energy X-ray absorptiometry (DXA, previously DEXA) study: An enhanced form of X-ray technology used to measure bone loss.

Duration of response (DoR): The length of time from onset of response to disease progression or death.

Dyspnea: The medical term for shortness of breath, often described as an intense tightening in the chest, air hunger, difficulty breathing, or breathlessness. Dyspnea can be caused by a number of medical problems, including anemia, pneumonia, or a pulmonary embolism.

E

Edema: An abnormal accumulation of fluid within body tissues. For example, peripheral edema is excess fluid that causes swelling in the ankles, feet, and legs.

Efficacy: Ability of treatment to produce a beneficial effect.

Electrolytes: Minerals in your blood and other body fluids that carry an electrical charge and are essential for life. Electrolytes include sodium, potassium, calcium, magnesium, chloride, phosphate, and bicarbonate. They affect the amount of water in the body, the acidity of the blood (pH), nerve and muscle function (including the heart), and other important processes.

Electrophoresis: A laboratory test used both for diagnosis and for monitoring of myeloma. Serum protein electrophoresis (SPEP) or urine protein electrophoresis (UPEP) testing enables both the calculation of the amount of myeloma protein and the identification of the type of M-spike for each patient.

Embryo-fetal toxicity: Exposure of an embryo or a fetus to a toxic substance. Females of reproductive potential and males with female partners of reproductive potential should ask the treating doctor if the use of effective contraception is necessary before treatment begins, during treatment, and/or after the last dose of treatment is administered.

Encephalopathy: Any brain disease that alters brain function or structure. Causes may include infection, tumor, or stroke. Symptoms may include reduced ability to reason or concentrate, memory loss, personality change, twitching, or seizures.

Engraftment: During the transplant process, engraftment takes place when the stem cells infused into the patient migrate from the bloodstream to the bone marrow, where they begin to produce new blood cells to replace the normal stem cells destroyed by high-dose therapy (HDT).

Enzyme: A protein molecule made by a cell, it triggers an increase in the rate of specific biochemical reactions in the body.

Eosinophil: A type of white blood cell that can signal the presence of parasites, allergies, or cancer. Eosinophils can also regulate allergic response.

Erythrocytes: Red blood cells (RBCs). RBCs carry oxygen to body cells and carbon dioxide away from body cells.

Erythropoiesis: The formation of new red blood cells.

Erythropoietin: A hormone produced by the kidneys that stimulates the production of red blood cells. Myeloma patients with damaged kidneys don’t produce enough erythropoietin and can become anemic.

Esophagitis: Inflammation of the esophagus, which is the tube that transports food from the mouth to the stomach.

Event-free survival (EFS): The length of time that a patient is free of myeloma recurrence, progression, complication, or death.

Extramedullary disease (EMD): Myeloma is primarily a disease of the bone marrow, but it can escape outside of the bone and to other parts of the body. EMD may be higher risk and more aggressive than myeloma that is confined to the bone marrow.

Extramedullary plasmacytoma: A tumor of monoclonal plasma cells that is found in soft tissue outside of the bone marrow and separate from bone.

Extravasation: Passage or escape of a drug (such as intravenous chemotherapy) or bone cement (during vertebroplasty or kyphoplasty) into surrounding tissue.

FFacet joint: Each vertebra has two facet joints, one on each side, that are crucial for maintaining spinal stability. Facet joint damage can lead to reduced mobility and pain.

Fanconi syndrome: A type of kidney damage that affects how kidneys reabsorb certain essential substances. Can cause metabolic bone disease (MBD) that weakens bones.

Fatigue: Fatigue caused by cancer or cancer treatment is a distressing, persistent, subjective sense of tiredness or exhaustion that is not proportional to recent activity and interferes with usual functioning.

Febrile neutropenia: The development of fever, often with signs of infection, in a patient with neutropenia. Febrile neutropenia is usually treated with antibiotics even if an infectious source can’t be identified. See Neutropenia.

Fluorescence in situ hybridization (FISH): This test uses special gene probes that fluoresce (glow) and signal the presence or absence of chromosomal abnormalities in a sample of a patient’s bone marrow.

Flow cytometry: A technology used in cell counting, cell sorting, and biomarker detection by suspending cells in a stream of fluid and passing them through a laser.

Free light chain (FLC): A light chain may be bound to a heavy chain or it may be unbound (free). FLCs are components of a normally produced immune protein. The serum FLC (sFLC) blood test measures the kappa light-chain level, the lambda light-chain level, and the kappa/lambda ratio produced by the myeloma cells. Measuring the output of myeloma cells is an indirect but effective way to assess the amount and activity of the disease. See Light chain and Heavy chain.

Frontline therapy: A general term for the initial treatment used in an effort to achieve response in a newly diagnosed myeloma patient. See Induction therapy and Response or remission.

G

Gastrointestinal (GI) side effects: Nausea, vomiting, diarrhea, constipation, bloating, or any other side effects that affect the digestive tract.

Gene: A specific sequence of DNA coding for a particular protein.

Gene therapy: Treatment that alters the activity of genes. This usually implies adding or removing a gene or genes.

Generic drug name: A brand name identifies a drug as property of the company that receives approval for it from a governmental regulatory agency, such as the U.S. Food and Drug Administration (FDA). After a drug goes off patent, other companies may make generic versions of the drug under a generic name that refers to the chemical makeup of a drug.

Genetic: Relating to genes or heredity in all living organisms. The biological process by which characteristics are passed from parent to offspring through DNA in the genes.

Glaucoma: A disease associated with the buildup of pressure inside the eye that, if untreated, can result in vision loss and blindness.

Globulin: A protein made in the liver by the immune system. Globulins that play an important role in liver function, blood clotting, and fighting infection include alpha, beta, and gamma. M-protein secreted by myeloma cells is a gamma globulin.

Glycoproteins: Proteins on the outer surface of cells that have sugars (carbohydrates) attached to them. They function as receptor sites where other molecules may attach to the cell.

Grade: The toxicity criteria adopted in the United States by the National Cancer Institute (NCI) for cancer clinical trials includes:

• Grade 0 – no symptoms,

• Grade 1 – mild symptoms,

• Grade 2 – moderate symptoms,

• Grade 3 – symptoms requiring treatment,

• Grade 4 – symptoms requiring urgent intervention,

• Grade 5 – symptoms resulting in death.

Graft-versus-host disease (GVHD): An immune-related reaction of the donor’s tissue against the recipient’s tissue. GVHD may cause complications or may even be fatal.

Granulocyte: A type of white blood cell that kills bacteria. Neutrophils, eosinophils, and basophils are all types of granulocytes.

Growth factors: Drugs that stimulate blood stem cells to both grow and be released into the bloodstream.

Guillain-Barré syndrome (GBS): A rare neurological disorder in which the immune system mistakenly attacks part of the patient’s own network of nerves located outside of the brain and spinal cord. Cases of GBS can be mild (brief weakness) or severe (paralysis). Most patients eventually recover but some will continue to have a degree of weakness.

Heavy chain: An immunoglobulin protein produced by plasma cells is made up of 2 heavy chains and 2 light chains, with the heavy chains being the larger of the two units. The 5 types of heavy chains (G, A, D, E, or M) are based on the class (isotype) of immunoglobulin produced by the myeloma cell. See Immunoglobulin (Ig).

Heavy chain deposition disease (HCDD): A rare type of monoclonal immunoglobulin deposition disease (MIDD) that is characterized by deposition of monoclonal heavy chains in organs. HCDD usually affects the kidneys but can also affect other organs.

Hematocrit (Hct): The percentage of red blood cells in the blood. A low hematocrit measurement indicates anemia.

Hematologic: Relating to the blood, originating in the blood, disseminated through the bloodstream.

Hematologic malignancy: A cancer of the bone marrow or blood cells.

Hematologist: A doctor who specializes in the problems of blood and bone marrow.

Hemoglobin: A protein in red blood cells that carries oxygen.

Herpes simplex: A common virus that causes sores, often seen around the mouth, commonly called cold sores.

Herpes zoster: Also called shingles, herpes zoster is caused by the reactivation of the varicella-zoster virus (VZV), the same virus that causes varicella (also called chickenpox). When reactivated, the herpes zoster infection frequently affects nerves.

High-risk multiple myeloma (HRMM): To assess treatment intensity, treatment duration, and clinical trial enrollment, patients with myeloma are divided into two groups, Standard-Risk (approximately 80% of patients) and High-Risk (approximately 20%). HRMM is a more aggressive form of myeloma that is more likely to be resistant to treatment, to relapse more quickly, and to feature specific genetic Chromosomal abnormalities.

Hormones: Chemicals produced by various glands that regulate the actions of certain cells or organs in the body.

Human leukocyte antigen (HLA) test: A blood test used to match a blood, tissue, or organ donor to a recipient for transfusion or transplant.

Hydroxyapatite: A compound that helps form bones and gives them rigidity and strength.

Hypercalcemia: A higher than normal level of calcium in the blood. In myeloma patients, it usually results from bone breakdown with release of calcium from the bone into the bloodstream. This condition can cause a number of symptoms, including loss of appetite, nausea, thirst, fatigue, muscle weakness, restlessness, and confusion. See Calcium.

Hypersensitivity reaction: Undesirable reactions, sometimes in response to a medication, produced by the normal immune system, including allergies and autoimmunity. These reactions may be uncomfortable, damaging, or fatal.

Hypertension: A chronic medical condition in which the blood pressure in the arteries is elevated. Also known as high blood pressure.

Hyperviscosity syndrome (HVS): When blood becomes so thick that the reduced blood flow in smaller vessels causes complications, which can be life-threatening. Treatment and management include intravenous fluids and plasmapheresis.

Hypogammaglobulinemia: A laboratory diagnosis made when the immune system is not producing enough immunoglobulin G (IgG) in the blood.

Hyponatremia: A low level of sodium in the blood. Symptoms include nausea, headache, confusion, and fatigue. Hyponatremia can be caused by fluid loss through vomiting or diarrhea, and also by fluid overload from heart, liver, or kidney disease.

Hyposecretory myeloma: See Oligosecretory myeloma and Non-secretory myeloma.

Hypoxia: A low level of oxygen in body tissues. Symptoms of hypoxia may include confusion, restlessness, difficulty breathing, rapid heart rate, and bluish skin.

IIkaros: A family of proteins that are highly expressed in myeloma and other B-cell cancers, where they are required for the growth and survival of cancer cells. Ikaros proteins are also important in the mechanism of action of immunomodulatory agents.

Immune effector cell-associated neurotoxicity syndrome (ICANS): A syndrome that can occur in the days or weeks after the administration of immunotherapy, especially immune effector cell (IEC) and T-cell therapies.

Immune system: A complex network of cells, tissues, organs, and the substances they make. The immune system involves multiple mechanisms that work together to protect and defend the human body from external threats (e.g., bacteria, viruses, toxins) and from internal threats (e.g., cancer). The immune system helps to destroy infected and diseased cells and to remove cellular debris, while protecting healthy cells.

Immunization: The process by which a body becomes protected against a disease through vaccination. See Vaccination.

Immunoassay: A test to detect proteins in the blood, it relies on the ability of an antibody to bind only to the specific three-dimensional structure of an antigen. In myeloma, this test is commonly used to detect specific antibodies.

Immunodeficiency: A lowering of the body’s ability to fight off infection and disease.

Immunofixation electrophoresis (IFE): This immunologic test of the serum (sIFE) or urine (uIFE) is used to identify the patient’s type of myeloma – the specific heavy-chain M-protein type (G, A, D, E, or M) and/or the light-chain type of the M-protein (kappa or lambda).

Immunofluorescence: A test that directs fluorophores (fluorescent dyes) to specific targets within a cell in order to show the distribution of the target molecule in the test sample. In myeloma, immunofluorescence is typically performed to see the location of an antigen or an antibody on a myeloma cell.

Immunoglobulin (Ig): A protein produced by plasma cells; an essential part of the body’s immune system. Immunoglobulins attach to foreign substances (antigens) and assist in destroying them. The classes (isotypes) of immunoglobulins are IgG, IgA, IgD, IgE, and IgM. Each type of immunoglobulin has a different function in the body. See Antibody and Antigen.

• IgG, IgA – The two most common types of myeloma. The G and A refer to the immunoglobulin heavy chain produced by the myeloma cells.

• IgD, IgE – These types of myeloma occur less frequently.

• IgM – This is a rare type of myeloma. IgM myeloma is not the same as Waldenström macroglobulinemia.

Immunohistochemistry (IHC): The process of detecting antigens in cells. Immunohistochemical staining is used in the diagnosis of abnormal cells, such as those found in cancerous tumors.

Immunomodulatory agent: A drug that can modify, enhance, or suppress the functioning of the immune system. An immunomodulatory agent is sometimes called an immunomodulatory drug (IMiD®).

Immunosuppression: Weakening of the immune system that causes a lowered ability to fight infection and disease. Immunosuppression may occur both from the effect of myeloma on the immune system and from treatments for myeloma.

Immunotherapy: Treatment that enhances the body’s natural defenses to fight cancer.

Incidence: The number of new cases of a disease diagnosed each year.

Induction therapy: The initial treatment given to a patient in preparation for an autologous stem cell transplant (ASCT). See Frontline therapy and Line of therapy.

Inflammation: A protective response of the body against injury or disease.

Inflammatory: Relating to inflammation, a protective response of the body against injury or disease.

Informed consent: The process that requires a doctor to give a patient enough information about a procedure, strategy, or clinical trial – including the issues of risks, benefits, alternatives, and potential costs – for the patient to make an informed decision about whether or not to consent to a particular treatment.

Infusion: Delivering fluids or medications into the bloodstream over a period of time.

Infusion pump: A device that delivers measured amounts of fluids or medications into the bloodstream over a period of time.

Infusion-related reaction (IRR): A type of hypersensitivity reaction that develops during or shortly after an intravenous (IV) infusion. IRRs are caused by cytokines and can occur with many IV cancer therapies. Reactions are often flu-like, and include nasal congestion, fever, chills, cough, throat irritation, shortness of breath, low blood pressure, nausea, and rash. See Administration-related reaction (ARR) and Cytokine.

Inhibit: To stop something or hold it in check.

Injection: The use of a syringe and needle to introduce a medication into the body.

Interferon: A naturally produced hormone (cytokine) released by the body in response to infection or disease that stimulates the growth of certain disease-fighting blood cells in the immune system. Interferon can be artificially produced by genetic engineering techniques and used as a form of immunotherapy.

Interleukin: A naturally produced chemical released by the body or a substance used in biological therapy, interleukins can stimulate the growth and activity of certain white blood cells. Interleukin-2 (IL-2) can stimulate the growth of blood cells in the immune system that can fight some types of cancer. Interleukin-6 (IL-6) stimulates osteoclast and plasma cell growth.

Interventional radiology: The branch of radiology concerned with providing diagnosis and treatment of disease by a variety of procedures performed through the skin under the guidance of radiologic imaging.

Intravenous immunoglobulin (IVIG): A medical product of concentrated human antibodies that can be delivered to a patient by Intravenous (IV) infusion or Subcutaneous (SQ) injection. Each IVIG dose is produced from the collected blood donated by thousands of people.

Intravenous (IV) infusion: Administered into a vein.

Ischemic events: An event caused by an inadequate supply of blood to an organ or tissues, such as from an obstructed blood flow. Myocardial ischemia occurs when blood supply to the heart is reduced, preventing it from receiving enough oxygen. This can cause damage to the heart muscle.

K

Keratopathy: Any noninflammatory disease of the cornea, the eye’s protective outer layer.

Kyphoplasty: A minimally invasive surgical procedure in which liquid cement is injected into a fractured or collapsed vertebra using a balloon technique. This can reduce pain and stabilize the spine. See Vertebral compression fracture (VCF).

Kyphosis: An exaggeration of the normal curve of the spine.

L

Lactate dehydrogenase (LDH): An enzyme present in nearly all of the tissues in the body. The serum LDH (sLDH) blood test is used to monitor myeloma activity.

Lesion: An area of abnormal tissue; a lump or abscess that may be caused by injury or disease, such as cancer. In myeloma, lesion can refer to a plasmacytoma or a hole in the bone.

• Diffuse lesion – A spread-out pattern of myeloma bone marrow involvement in an area of bone.

• Focal lesion – An abnormal area seen in the bone marrow on MRI or PET-CT study. In order to be considered a myeloma-defining event, there must be more than 1 focal lesion of at least 5 mm in size.

• Lytic lesion – The damaged area of a bone that appears as a dark spot on an X-ray when at least 30% of the healthy bone in any one area is eaten away. Lytic lesions look like holes in the bone and are evidence that the bone is being weakened. See Lytic (lysis).

Leukapheresis: See Apheresis.

Leukocytes: Cells that help the body fight infections and other diseases. Also called White blood cells (WBC).

Leukopenia: A low number of white blood cells.

Ligase: An enzyme that can join two molecules by forming a new chemical bond.

Light chain: An immunoglobulin light chain is the smaller of the two units of an antibody. The light chains are bound by chemical bonds to the ends of the heavy chains, but we make extra light chains that enter the bloodstream. These are called free light chains. There are two types of light chains: kappa and lambda. See Free light chain (FLC).

Light chain deposition disease (LCDD): A rare type of monoclonal immunoglobulin deposition disease (MIDD) that is characterized by deposition of complete or partial monoclonal light chains in organs. LCDD usually affects the kidneys but can also affect other organs. The goal of treating LCDD is to slow damage to organs.

Light chain escape: An increase of free light chains at the time of relapse without corresponding increase of the intact monoclonal immunoglobulin.

Line of therapy: The sequence of distinct treatment approaches received by a patient from the point of active disease until treatment is stopped or changed to a different approach. A line of therapy can consist of one drug, a combination of several drugs, or a planned order of drugs. For example, one line of therapy can include Frontline therapy with Induction therapy followed by Transplant (or not) and Maintenance therapy. Drug approvals by the U.S. Food & Drug Administration (FDA) specify how many prior lines of therapy a patient must have before receiving a particular drug. Clinical trials always specify the required number of prior lines of therapy to qualify for study enrollment.

Lumbar vertebrae: The five lumbar vertebrae bones form the spine in the lower back, between the rib cage and the pelvis.

Lupus: See Systemic lupus erythematosus (SLE).

Lymphatic system: Also called lymphoid system, is a subsystem of the circulatory system that includes our lymph nodes and the channels that connect them. One of its main functions is the production and circulation of immune cells (e.g., lymphocytes, monocytes, and plasma cells). Lymphoid organs include the bone marrow and the thymus.

Lymphocytes: B cells (B lymphocytes), T cells (T lymphocytes), and natural killer (NK) cells that together constitute 30% of white blood cells (WBC).

Lymphopenia: Also called lymphocytopenia, this is a low level of B cells (B lymphocytes), T cells (T lymphocytes), and natural killer (NK) cells.

Lytic (lysis): Dissolution or destruction of cells or tissues.

M-spike: A monoclonal spike, the sharp pattern that occurs on protein electrophoresis tests. M-spike is a marker for the activity of myeloma cells. See Monoclonal and Monoclonal protein (myeloma protein, M-protein).

Macrophage: An immune system cell whose job it is to engulf and devour any cell (including a cancer cell) that does not have proteins on its surface to identify it as a healthy body cell.

Magnetic resonance imaging (MRI): Diagnostic imaging that uses magnetic fields and radio waves to produce detailed 2D or 3D images of structures inside the body. MRI can reveal the presence and distribution of myeloma in the bone marrow when X-rays show no damage. MRI can reveal myeloma outside of bone. MRI gives fine resolution of soft tissues, especially encroachments on the spinal cord.

Maintenance therapy: Drug or drugs given to patients to prolong remission.

Malignant: Cancerous; capable of invading nearby tissue and spreading to other parts of the body.

Maximum-tolerated dose (MTD): The highest dose of a drug or treatment that does not cause unacceptable side effects.

Mechanism of action (MOA): The biochemical process through which a drug or molecule produces an effect in the body.

Median: Statistically, this term represents the 50th percentile, the midpoint in a set of data. In clinical trials, this is the time when half of the study patients meet the endpoint being studied, such as median progressionfree survival (mPFS) or median survival.

Melanoma: A cancer of the pigment-forming cells of the skin or the retina of the eye. Not associated with myeloma despite the similar-sounding name.

Meta-analysis: An analysis that combines, or pools, the data from multiple scientific studies.

Metabolism: The conversion of one compound into another compound, which occurs during a living organism’s life-sustaining chemical processes. See Metabolite.

Metabolite: Any substance that is formed during metabolism or that is necessary for metabolism. See Metabolism.

Metabolize: When the body or an organ of the body converts one compound into another by the process of metabolism. See Metabolism.

Metastasis: The spread of cancer cells from one part of the body to another. The term usually refers to solid tumors and not to myeloma, which is a blood-related cancer.

Minimal residual disease (MRD): The presence of residual tumor cells after treatment has been completed and complete response (CR) has been attained. Even patients who have attained a stringent CR (sCR) may have MRD. Highly sensitive testing methods are able to detect 1 myeloma cell among 1,000,000 sampled cells in blood or bone marrow.

• MRD-negative – Minimal residual disease-negative. Depending on the test, not even one myeloma cell found in 100,000 or 1,000,000 sampled bone marrow plasma cells.

• Sustained MRD (sMRD) rate – The proportion of patients with MRDnegative results, and without any MRD-positive results in between. Ask your doctor what period of time is considered sustained in your situation (e.g., 6 months, 12 months, or longer).

Mobilizing agent: An agent injected into a patient or donor to trigger the release of bone marrow stem cells into the bloodstream.

Molecule: The smallest particle that retains all the properties of a substance. A molecule is an electrically neutral group composed of two or more atoms held together by chemical bonds.

Monoclonal: A monoclone is a duplicate derived from a single cell. Myeloma cells are monoclonal, derived from a single malignant plasma cell in the bone marrow. The type of myeloma protein produced is also monoclonal, a single form rather than many forms (polyclonal). The important practical aspect of a monoclonal protein is that it shows up as a sharp spike on the protein electrophoresis test. See M-spike.

Monoclonal antibody: An antibody manufactured in a lab rather than produced in the human body. Monoclonal antibodies are specifically designed to find and bind to cancer cells and/or immune system cells for diagnostic or treatment purposes. Monoclonal antibodies can be used alone, or they can be used to deliver drugs, toxins, or radioactive material directly to tumor cells.

Monoclonal gammopathy of undetermined significance (MGUS): A benign plasma cell disorder characterized by comparatively low levels of monoclonal protein in the blood and/or urine. Bone marrow plasma cell levels are less than 10% and SLiM-CRAB criteria features are absent. See Benign and SLiM-CRAB criteria.

Monoclonal immunoglobulin deposition disease (MIDD): Caused by deposition of heavy chains, light chains, or both heavy and light chains. See Light chain deposition disease (LCDD) and Heavy chain deposition disease (HCDD).

Monoclonal protein (myeloma protein, M-protein): An abnormal protein produced by myeloma cells that accumulates in and damages bone and bone marrow. It is found in unusually large amounts in the blood and/or urine of myeloma patients. See Monoclonal and M-spike.

Monocyte: A type of white blood cell. Monocytes migrate from the bloodstream to other tissues. Monocytes present in tissue are also called macrophages. They engulf and devour any cell (including a cancer cell) that does not have proteins on its surface to identify it as a healthy body cell.

Monotherapy: Therapy that uses a single drug to treat a disease or condition. This term also describes a single type of treatment used, such as surgery alone or radiation therapy alone.

Multi-drug resistance (MDR): Resistance to a wide range of structurally unrelated treatment compounds.

Multiple myeloma: A cancer of the bone marrow plasma cells, white blood cells that make antibodies. Cancerous plasma cells are called myeloma cells.

Myelin sheath: A protective membrane that forms around nerve fibers, then speeds the transmission of electrical impulses efficiently along the nerve cells.

Myeloablation: A severe form of myelosuppression, in which the consequence of high-dose chemotherapy or radiation is the complete or near-complete destruction of the bone marrow’s ability to produce blood cells. See Myelosuppression.

Myelodysplastic syndrome (MDS): A condition in which the bone marrow does not function normally and does not produce enough blood cells. This condition can occasionally progress and become acute leukemia.

Myeloid: Referring to myelocytes, a type of white blood cell. Also called myelogenous. Myeloma is a lymphoid cancer, not a myeloid cancer.

Myeloma-defining event (MDE): See SLiM-CRAB criteria.

Myelosuppression: A decrease in the production of red blood cells, platelets, and some of the white blood cells.

Natural killer (NK) cell: A type of white blood cell that is able to recognize cells transformed by tumors and can induce a strong response against tumors through the release of cytokines. In patients with active myeloma, NK cells are reduced both in number and in function.

Necrosis: The death of living tissues.

Neoplasia: Abnormal new growth of cells; cancer.

Neoplasm: Abnormal new growth of tissue or cells creating a malignant tumor.

Nephrotic syndrome: A group of diseases characterized by excretion of large amounts of protein (mostly albumin) into urine. Nephrotic syndrome frequently produces edema.

Nephrotoxicity: The quality of being toxic or destructive to kidney cells.

Neuropathy: A feeling of numbness, tingling, burning, and/or pain caused by nerve damage.

• Peripheral neuropathy (PN) – A serious condition that affects nerves in the hands, feet, lower legs, and/or arms. PN can occur from the effects of the myeloma itself or from treatments for myeloma.

Neurosurgeon: A doctor who performs surgery on any part of the nervous system, including the back and the spinal cord.

Neurotoxicity: Neurologic toxicity is when exposure to toxic substances changes the normal activity of the nervous system.

Neutropenia: A reduced level of neutrophils, a type of white blood cell necessary to fight infection caused by bacteria or fungi. Fever is the most common sign of neutropenia that requires immediate medical attention.

Neutrophil: A type of cell that constitutes about 60% of white blood cells. Neutrophils fight infection caused by bacteria or fungi. See Neutropenia.

Next-generation flow (NGF): A cytometry test that is a highly accurate way to detect Minimal residual disease (MRD) after treatment, uses myeloma-specific computer software to perform eight-color immunophenotyping of myeloma cells. NGF can detect 1 myeloma cell per approximately 1,000,000 bone marrow cells in a laboratory sample.

Next-generation sequencing (NGS): A highly precise test that analyzes DNA from a sample of bone marrow to determine if myeloma is present. NGS compares the DNA sequence to the patient’s original bone marrow sample. NGS can detect 1 myeloma cell among 1 million normal cells (10 -6) and is used to monitor the patient’s Minimal residual disease (MRD).

Non-secretory myeloma: Approximately 98% of myeloma patients have measurable M-protein at the time of diagnosis. Approximately 1%–2% of patients have non-secretory myeloma with no evidence of M-protein as determined by serum protein electrophoresis (SPEP), serum immunofixation electrophoresis (sIFE), serum free light chain (sFLC), and urine protein electrophoresis (UPEP). Treatment options are the same regardless of M-protein amount. See Monoclonal protein (myeloma protein, M-protein).

Nonsteroidal anti-inflammatory drug (NSAID): A drug that works in a different way than a steroid to reduce pain, redness, swelling, and fever in the body.

Nucleus: In advanced organisms, the nucleus of the cell is the control center of the cell. It stores all the genetic material (DNA) of the cell and it coordinates the cell’s activities, including growth and reproduction (cell division).

O

Oligosecretory myeloma: Disease with low amounts of measurable M-protein, also known as hyposecretory. Patients with oligosecretory myeloma may require disease monitoring found effective for non-secretory patients. See Non-secretory myeloma.

Oncogene: A damaged (mutated) form of a normal gene. An oncogene can be inherited or the result of environmental exposure. Oncogenes have the potential to cause normal cells to become cancerous.

Oncologist: A doctor who specializes in treating cancer. Some oncologists specialize in a particular type of cancer.

Orphan drug: The orphan drug designation is granted by the U.S. Food and Drug Administration (FDA) to provide incentives such as tax credits, user fee waivers, and eligibility for orphan drug exclusivity to assist and encourage the development of drugs for rare diseases.

Orthopedic surgeon: Orthopedic surgeons use both surgical and nonsurgical means to treat musculoskeletal trauma, sports injuries, degenerative diseases, infections, tumors, and congenital disorders.

Orthostatic hypotension: Feeling dizzy or light-headed when blood pressure drops after suddenly standing up from a lying or sitting position. Can lead to fainting.

Osteoblast: A bone cell associated with production of bone tissue. Osteoblasts produce osteoid, which then becomes mineralized with calcium to form new hard bone.

Osteoclast: A cell found at the junction between the bone marrow and the bone. It is responsible for breaking down or remodeling old bone tissue. In myeloma, the osteoclasts are overstimulated, while osteoblast activity is blocked. The combination of accelerated bone resorption and blocked new bone formation results in bone disease (lytic lesions).

Osteoid: The protein produced by osteoblasts which becomes mineralized with calcium to form hard bones.

Osteonecrosis of the jaw (ONJ): A jaw problem observed in a small percentage of patients taking bone-modifying agents (BMAs), such as bisphosphonates. ONJ can cause pain, swelling, jaw numbness or heaviness, and bone damage around the tooth socket. Bone necrosis (death) can lead to loosened teeth, sharp edges of exposed bone, bone spurs, and the breaking loose of small bone spicules. ONJ is defined as non-healing exposed bone for 3 months or longer.

Osteopenia: A condition in which bone mineral density is lower than normal, but not low enough to be classified as osteoporosis.

Osteoporosis: A progressive bone disease that is characterized by a decrease in bone mass and density, leading to an increased risk of fracture. Myeloma bone disease may look like osteoporosis on X-ray and bone density measurement.

Over-the-counter (OTC) medication: OTC products can be purchased without a prescription.

Overall response rate (ORR): In myeloma clinical trials, the percentage of patients whose monoclonal protein decreased by at least 50% in response to treatment.

Overall survival (OS): In a clinical trial, this represents the amount of time measured from diagnosis or start of treatment until death from any cause. Historically, OS is considered to be the gold standard for assessing if a treatment extends a patient’s life. As myeloma therapies become more effective and the length of OS duration is increased, clinical trials can use faster endpoints to validate outcomes. See Minimal residual disease (MRD) and Progression-free survival (PFS).

• Median OS – The time point at which 50% of patients are still alive.

• OS rate – The percentage of patients alive at a specific time (e.g., 10-year survival rate).

Palliative treatment: A treatment designed to improve the quality of life by relieving pain and symptoms of disease but not intended to alter the course of the disease.

Paracrine: In a paracrine loop, factors produced by the microenvironment surrounding myeloma cells can stimulate these cells, which in turn stimulate the microenvironmental cells. Also see Autocrine.

Partial response: See Response or remission.

Pathogen: An infectious agent that causes disease in its host (e.g., virus, bacterium, fungus, parasite).

Pathologic fracture: A break in a bone usually caused by cancer or some disease condition. Occurs in myeloma-weakened bones, which can’t bear normal weight or stress.

Pathologist: A doctor who specializes in pathology, the study of disease by the examination of tissues and body fluids under the microscope.

Performance status: Also called ECOG status. A measure of the level of activity of which a patient is capable and, by implication, a measure of the severity of disease. The ECOG scale runs from 0 (fully active and able to carry on all pre-disease activities without restriction) and to 5 (death). Many clinical trials require ECOG status of 0 or 1; studies enrolling patients with a status of 3 or 4 are rare.

Peripheral blood stem cells (PBSC): Stem cells collected from the circulating blood. These cells are similar to stem cells found in the bone marrow. The term peripheral means that the cells come from blood outside of the marrow.

Peripheral blood stem cell transplant: See Transplant (transplantation).

Peripheral nervous system (PNS): All the nerves in the body beyond the brain and the spinal cord. See Central nervous system (CNS).

Pharmacodynamics (PD): The study of the biochemical, physiologic, and molecular effects of a drug on an organism.

Pharmacogenomics (PG): The study of how genes affect response to a drug or treatment. Also called pharmacogenetics.

Pharmacokinetics (PK): The study of the processes by which a drug is absorbed, distributed, metabolized, and eliminated by the body.

Phlebitis: Inflammation of a vein.

Photophobia: When an extreme sensitivity to light is a symptom of another problem.

Placebo: An inert (inactive) substance often used in clinical trials for comparison with an experimental drug. No clinical trial for cancer patients in the U.S. can ethically or legally randomize patients to receive a placebo alone when they require treatment. In the placebo arm of a cancer treatment trial, patients receive treatment with approved therapy plus a placebo.

Plasma: The liquid part of the blood in which red blood cells, white blood cells, and platelets are suspended.

Plasma cells: White blood cells that produce antibodies. Myeloma cells are cancerous plasma cells, which produce monoclonal protein (myeloma protein, M-protein) that can lead to organ and tissue damage (anemia, kidney damage, bone disease, and nerve damage).

Plasma cell dyscrasias (PCDs): A type of blood cancer in which plasma cells become malignant and infiltrate the bone marrow. PCDs can be clinically indolent or aggressive. PCDs include multiple myeloma.

Plasmacytoma: See Extramedullary plasmacytoma and Solitary plasmacytoma of bone (SPB).

Plasmapheresis: The process of removing specific proteins from the bloodstream. For example, plasmapheresis can be used to remove high levels of M-protein from the bloodstream of myeloma patients with kidney failure.

Platelets: One of the three major types of blood cells, the others being red blood cells and white blood cells. Platelets plug up breaks in the blood vessel walls and release substances that stimulate blood clot formation. Platelets are the major defense against bleeding. Also called thrombocytes.

Port (implanted): A catheter connected to a disc that is surgically placed just below the skin in the chest or abdomen so that fluids, drugs, or blood products can be infused, and blood can be drawn through a needle that is inserted into the disc.

Positron emission tomography (PET): A sophisticated diagnostic test that uses a camera and computer to produce images of the body. PET scans show the difference between healthy and abnormally functioning tissues based upon the uptake of radiolabeled sugar by active cancer cells.

Precancerous: A term used to describe a condition that may or may not become cancer. See Monoclonal gammopathy of undetermined significance (MGUS).

Prognosis: The projected outcome or course of a disease; the chance of recovery; life expectancy.

Progression-free survival (PFS): The length of time during and after the treatment of myeloma that a patient lives with the disease but the myeloma does not get worse. In a clinical trial, PFS is one way to measure how well the treatment is working. See Progressive disease.

Progressive disease: Myeloma that is becoming worse or relapsing, as documented by tests. Defined as an increase of ≥ 25% from the lowest confirmed response value in the myeloma protein level and/or new evidence of disease.

Prophylactic: A measure or medication taken to prevent or reduce the severity of a specific condition.

Proteasome: A joined group (“complex”) of enzymes (“proteases”) that break down the damaged or unwanted proteins in both normal cells and cancer cells into smaller components. Proteasomes also carry out the regulated breakdown of undamaged proteins in the cell, a process that is necessary for the control of many critical cellular functions. These smaller protein components are then used to create new proteins required by the cell. This is important for maintaining balance within the cell and for regulating cell growth.

Proteasome inhibitor: Any drug that interferes with the normal function of the proteasome. See Proteasome.

Proteins: Substances composed of amino acids. Proteins are an essential part of all living organisms, especially as structural components of body tissues such as muscle, hair, collagen, etc., as well as enzymes and antibodies.

Protocol: A detailed treatment plan, which includes the dose and schedule of any drugs used.

Pulmonary embolism (PE): A potentially life-threatening condition that occurs when a blood clot in a vein (deep vein thrombosis, or DVT) breaks loose, travels through the bloodstream, and gets stuck in an artery in a lung, blocking blood flow.

Pyrexia: Fever of 100.4°F (38°C) or higher.

RRadiation therapy: Treatment with X-rays, gamma rays, or electrons to damage or kill malignant cells. Radiation may be delivered from outside the body or from radioactive materials implanted directly in the tumor.

Radiologist: A medical doctor who interprets images produced with X-rays, sound waves, magnetic fields, and other types of energy.

Recurrence: The reappearance of a disease after a period of remission.

Red blood cells (RBC): Also called erythrocytes, RBCs contain hemoglobin, deliver oxygen to all parts of the body, and take away carbon dioxide. RBC production is stimulated by a hormone (erythropoietin) produced by the kidneys. People with damaged kidneys don’t produce enough erythropoietin and can become anemic. Myeloma patients can also

become anemic because of myeloma cells’ effect on the ability of bone marrow to make new RBCs.

Refractory: Disease that is no longer responsive to standard treatments. Myeloma is refractory in patients who have had progressive disease either during treatment or within 60 days following treatment. Many myeloma clinical trials enroll patients with relapsed or refractory disease.

Registration trial: The U.S. Food and Drug Administration (FDA) is the regulatory agency for drugs sold in America. As a prerequisite to approval and sale of a product, the FDA requires that a well-controlled registration clinical trial provides evidence of the drug’s safety and efficacy.

Relapse: The reappearance of signs and symptoms of myeloma after a period of improvement. Patients with relapsed disease have been treated, then developed signs and symptoms of myeloma at least 60 days after treatment ended.

Response or remission: Interchangeable terms to describe the complete or partial disappearance of the signs and symptoms of cancer.

• Stringent complete response (sCR) is CR (as defined below) plus normal FLC ratio and absence of clonal cells in bone marrow by immunohistochemistry or immunofluorescence.

• Complete response (CR) is negative immunofixation on serum (blood) and urine, and disappearance of any soft tissue plasmacytomas, and ≤ 5% plasma cells in bone marrow.

• Very good partial response (VGPR) is serum M-protein and urine M-protein detectable by immunofixation but not on electrophoresis, or 90% or greater reduction in serum M-protein, plus urine M-protein less than 100 mg per 24 hours.

• Partial response (PR) is a level of response in which there is at least a 50% reduction in M-protein, and reduction in 24-hour urinary M-protein by at least 90% (or to less than 200 mg per 24 hours).

• Minimal response (MR) is a 25%–49% reduction of serum M-protein and reduction in 24-hour urine M-protein by 50%–89% and, if present at baseline, a reduction in the size of plasmacytomas is also required.

Ribonucleic acid (RNA): Any of various nucleic acids that are associated with the control of cellular chemical activities. RNA is one of the two nucleic acids found in all cells – the other is DNA (deoxyribonucleic acid). RNA transfers genetic information from DNA to proteins produced by the cell.

Risk evaluation and mitigation strategy (REMS): The U.S. Food and Drug Administration (FDA) requires a REMS program for treatments that may have serious safety concerns. REMS programs support the use of such treatments and help ensure that the potential benefits outweigh the risks.

Risk stratification: In 2025, the IMF International Myeloma Working Group (IMWG) and the International Myeloma Society (IMS) published the IMWG-IMS classification of risk that uses recent research data to divide myeloma into two groups: Standard-Risk and High-Risk.

SSacrum: A triangular-shaped bone located below the lumbar spine and above the coccyx (tailbone). The sacral region is comprised of five fused vertebrae (S1-S5) that form a wedge between the hip bones.

Safety population: A set of patients in a clinical trial who are grouped for analysis according to the treatment they received. Analysis includes safety and adverse events, toxicity and laboratory evaluations.

Salvage therapy: A treatment regimen that is given after the patient’s disease does not respond to preferred therapies or the patient cannot tolerate other available therapies.

Scleroderma: A connective tissue disorder characterized by tightening of the skin of the arms, face, or hands; puffy hands and feet; and joint stiffness. It can affect the entire body or just one part.

Second primary malignancy (SPM): A new cancer that is unrelated to a pre-existing cancer diagnosis. Secondary cancers that are a consequence of treatment for the initial cancer may occur months or years after the initial treatment.

Selective inhibitor of nuclear export (SINE): A compound that prevents cells from expelling tumor suppressor proteins, which help protect the cell from cancer. When tumor suppressors accumulate in a myeloma cell, they can counteract the pathways that allow cancer cells to grow and divide, which leads to myeloma cell death. Also known as XPO1 inhibitors.

Sepsis: The body’s potentially life-threatening response to an infection. Sepsis occurs when bacteria, viruses, fungi, or other infectious organisms or toxins, which are created by infectious organisms in the bloodstream, spread throughout the body. Sepsis can lead to tissue damage, organ failure, and death. Sepsis can progress to septic shock, which is more likely to cause death than sepsis.

Serum: The colorless, liquid part of blood in which the blood cells are suspended.

Serum osteocalcin: A protein produced and secreted by osteoblasts when they are making osteoid. A low level reflects active myeloma. A higher-thannormal level reflects more stable myeloma.

Serum sickness: A hypersensitivity reaction caused by the administration of a foreign serum; it causes fever, swelling, skin rash, and enlargement of the lymph nodes.

Shingles: See Herpes zoster.

Side effect: An unwanted or unexpected effect caused by a drug. Also known as adverse reaction or adverse event (AE).

Skeletal-related event (SRE): Bone damage or fracture.

Skeletal survey (metastatic survey): A series of plain X-rays of the skull, spine, ribs, pelvis, and long bones to look for lytic lesions and/or osteoporosis.

SLiM-CRAB criteria: The diagnosis of myeloma requires evidence of at least 10% monoclonal plasma cells in the bone marrow or biopsy-proven bony or extramedullary plasmacytoma PLUS at least one of the following myeloma-defining events (MDE):

Sixty percent (60%) or more monoclonal plasma cells in the bone marrow.

Light chains ratio of involved-to-uninvolved sFLC of 100 or more.

MRI imaging of 2 or more focal lesions in the bone marrow.

Calcium level elevation in the blood due to myeloma.

Renal (kidney) damage due to myeloma.

Anemia (low hemoglobin) due to myeloma.

Bone damage related to myeloma.

Smoldering multiple myeloma (SMM): A diagnosis of SMM requires 10% or more clonal plasma cells in the bone marrow as well as the absence of Myeloma-defining events (MDE). The healthcare team monitoring a person diagnosed with SMM should include a myeloma specialist. Standardrisk SMM does not require treatment, but patients with high-risk SMM (HR-SMM) should discuss with their doctor if treatment could be beneficial.

Solid tumor: A mass that develops in organs, bones, or soft tissues. Can be Benign or Malignant .

Solitary plasmacytoma of bone (SPB): This is a rare cancer of unknown origin, a single mass of monoclonal plasma cells in a bone or bone marrow. Fewer than 1,000 people in the U.S. are diagnosed with SPB each year. SPB is NOT myeloma. In fact, SPB diagnosis requires the absence of systemic myeloma. However, the majority of people with SPB are eventually diagnosed with myeloma.

Spinal cord: A long, thin, tubular bundle of nervous tissue and support cells that extends from the brain. The brain and spinal cord together make up the central nervous system. The spinal cord begins at the occipital bone and extends down to the space between the first and second lumbar vertebrae.

Spine: The spine, a collection of bones that make up the neck and back, is divided into four main regions: The cervical spine (neck region) is comprised of 7 vertebrae (C1 through C7, top to bottom). The thoracic spine (chest region) is comprised of 12 vertebrae (T1 through T12). The lumbar spine (lower back) is comprised of 5 vertebrae (L1 through L5). The sacrum is a triangular-shaped bone located below the lumbar spine and above the coccyx (tailbone).

Stable disease (SD): Myeloma that has neither improved nor worsened. Myeloma can remain stable for many years. See Response or remission and Progressive disease.

Staging: The staging system used for solid tumors does not apply to blood-based cancers like myeloma. In 1975, the Durie-Salmon Staging System became the first to classify patients with myeloma based on the correlation between the amount of myeloma and the damage caused by it. Currently, the system used to provide guidance to doctors in the evaluation and treatment of people with myeloma is Risk stratification.

Standard of care (SOC): This a legal term, not a medical term, and its definition may vary based on jurisdiction or country. SOC is a benchmark treatment that is widely accepted by medical experts as the most appropriate to be used by healthcare professionals in a particular setting. SOC therapies for patients with myeloma are evolving as newer and more effective treatments become available, setting new benchmarks. SOC may also be called best practice, best available therapy, or standard therapy. When new treatments are being evaluated in clinical trials, they are generally compared with SOC or evaluated as an addition to SOC.

Stem cell selection: A cell processing technology that is used to obtain a stem cell-enriched product and thereby reduce cancer cells in the transplant. Not used successfully for myeloma patients.

Stem cells (hematopoietic stem cells): The immature cells from which all blood cells develop. Normal stem cells give rise to normal blood components, including red cells, white cells, and platelets. Stem cells are normally located in the bone marrow and can be harvested for transplant.

Steroid: Steroidal hormones are produced by the body. Synthetic analogues (equivalents) of some steroids can be manufactured in a laboratory. Synthetic steroids are used in the treatment of many conditions, including myeloma.

Subcutaneous (SQ) injection: A method of administering medication under the skin by a short needle that injects a drug into the tissue layer between skin and muscle.

Substrate: A molecule or substance upon which an enzyme acts to trigger a biochemical reaction. The enzyme-substrate interaction transforms the substrate into something new while the enzyme remains unchanged. See Enzyme.

Supportive care: Treatment given to prevent, control, or relieve complications and side effects and to improve the patient’s comfort and quality of life.

Synergistic: When two or more elements produce a combined effect that is greater than the sum of their separate effects.

Syngeneic transplant: See Transplant (transplantation).

Systemic lupus erythematosus (SLE): The most common type of lupus, an inflammatory autoimmune disorder in which the immune system attacks and damages its own tissues and organs. Lupus can affect the joints, skin, kidneys, brain, heart, lungs, and blood cells. There is no cure for SLE, but medical care and lifestyle changes can help manage it.

Systemic treatment: Treatment using substances that travel through the bloodstream to reach and affect cells in the entire body.

TT cell (T lymphocyte): A type of white blood cell. T cells are an important part of our immune system by helping the body fight infection and disease. T cells can be distinguished from other white blood cells by the presence of a T-cell receptor (TCR) on the cell surface. T cells can recognize and bind to specific antigens, thereby triggering an immune response.

Tachycardia: A heart rate that is more than 100 beats a minute. Tachycardia may not cause any symptoms and may not be a concern, such as during exercise or as a response to stress. But some forms of tachycardia can lead to serious problems if left untreated, including heart failure, stroke, or sudden cardiac death.

Thrombocytes: See Platelets.

Thrombocytopenia: A low number of platelets in the blood. Platelets help blood to clot; fewer platelets can lead to easier bruising, bleeding, and slower healing. The normal level of platelets varies from laboratory to laboratory. For example, at Mayo Clinic the normal level is 150,000 or more platelets per microliter of circulating blood. Bleeding problems could occur if the count is less than 50,000 platelets. Major bleeding is usually associated with a reduction to less than 10,000 platelets.

Time-to-progression (TTP): The time from start of treatment until relapse occurs.

Toxin: A poisonous substance produced by or derived from plant, animal, or microorganism origin (i.e., bacteria, fungi, algae).

Trabecular bone: Also known as cancellous bone; the light, porous bone enclosing numerous large spaces that give it a sponge-like appearance. Trabecular bone contains marrow and blood vessels.

Transfusion: The transfer of blood or blood products.

Transplant (transplantation): There are several different types of transplantation procedures to replace diseased bone marrow with healthy bone marrow.

• Autologous stem cell transplant (ASCT) – This is the type of transplant used most frequently in myeloma. After a patient receives induction therapy, stem cells are mobilized from the bone marrow into the bloodstream, where the stem cells are collected, then stored in a laboratory. The patient is treated with high-dose therapy (HDT) to kill the remaining myeloma cells. Then the patient’s own stem cells are infused back into the patient through a vein, and these stem cells travel to the bone marrow where they begin producing new blood cells.

• Bone marrow transplant – An autologous transplant with stem cells collected from a patient’s bone marrow, not from a patient’s bloodstream. Bone marrow transplantation is used infrequently in myeloma because ASCT is preferred, but it may be considered if stem cells are not able to be collected from the bloodstream.

• Allogeneic (allograft) transplant – Rarely used in myeloma, this type of transplant uses stem cells or bone marrow collected not from the patient, but from a donor who has been determined to be a compatible match with a recipient by means of a human leukocyte antigen (HLA) blood test. Donor cells are infused into the patient after the patient undergoes HDT. Unfortunately, while the donor’s immune system cells recognize the recipient’s myeloma cells as foreign and attack them, the donor’s cells also attack other tissues in the recipient’s body, causing GVHD, an immune-related reaction of the donor’s tissue against the recipient’s tissue. GVHD may cause complications or may even be fatal.

• Reduced-intensity conditioning (RIC) allogeneic transplant –This type of allogeneic transplant is sometimes called a mini-allo. For myeloma, a mini-allo is a safer technique than a full allogeneic transplant because it uses less intense chemotherapy. RIC transplant is usually performed within 180 days after a standard ASCT.

• Tandem transplant – ASCT can be performed once (a single autologous transplant) or twice (double or tandem autologous transplants). Tandem ASCTs are usually done with an interval of 3 to 6 months between the two transplants. Tandem transplantation for myeloma has become less common due to the emergence of effective novel therapies.

• Second ASCT – This is an option for patients who achieved response of at least an 18-month duration following their first ASCT. A second ASCT appears to be beneficial for some patients, and this is one of the reasons that enough stem cells for two ASCTs may be collected in advance of the first transplant.

• Syngeneic transplant – An allogeneic transplant where bone marrow or stem cells from one identical twin sibling (donor) are infused into the other identical twin (recipient).

• Matched unrelated donor (MUD) transplant – An allogeneic transplant where stem cells are genetically matched to the patient but are not from a donor who is a family member. In myeloma, this type of transplant carries a high risk of GVHD and is rarely used.

• Umbilical cord stem cell transplant – An allogeneic transplant where stem cells are harvested from multiple umbilical cords of newborns in order to obtain enough stem cells for an adult transplant. In myeloma, this type of transplant carries a high risk of GVHD and is rarely used.

Treatment emergent adverse event (TEAE): An event that emerges during treatment, having been absent before treatment, or an event that worsens relative to the pretreatment state.

Tumor: An abnormal mass of tissue that results from excessive cell division. In myeloma, a tumor is referred to as a plasmacytoma.

Tumor lysis syndrome (TLS): A disorder caused by the break-down products of dying cancer cells, which can overwhelm the kidneys and lead to kidney failure. TLS can occur when a patient responds very quickly and deeply to therapy. TLS is usually treated with allopurinol, a treatment for gout.

Tumor marker: A substance in blood or other body fluids that can serve as a measure of cancer. See Biomarker.

Tumor necrosis factor (TNF): A cell signaling protein (cytokine) involved in systemic inflammation and bone resorption. TNF alpha (TNF-α) is elevated in myeloma patients.

Tumor suppressor gene: A gene that protects a cell from one step on the path to cancer. When this gene mutates to cause a loss or reduction in its function, the cell can progress to cancer, usually in combination with other genetic changes. See Anti-oncogene.

V

Vaccination: The act of introducing a vaccine into a body to produce protection from a specific disease. A vaccine is a preparation of microorganisms that is administered to produce or increase immunity to a disease. See Immunization.

Vascular endothelial growth factor (VEGF): A growth factor that promotes the growth of new blood vessels (angiogenesis).

Venous thromboembolism (VTE): A condition that includes both deep vein thrombosis (DVT) and pulmonary embolism (PE). Risk factors include infection, age >75, cancer, and a history of VTE. See Deep vein thrombosis (DVT) and Pulmonary embolism (PE).

Vertebra: Any one of the 33 bony segments of the spinal column. Plural noun is vertebrae.

Vertebral body: The round bony area of a vertebra.

Vertebral compression fracture (VCF): A complication that may occur in a patient with myeloma bone disease when a vertebra of the spinal column fractures or collapses because the bone is too weak to withstand the pressure placed upon it by a fall, twist, bump, cough, sneeze, or the force of gravity acting upon the skeleton.

Vertebroplasty: A minimally invasive surgical procedure in which liquid cement is injected into a fractured or collapsed vertebra to reduce pain and to stabilize the spine after a vertebral compression fracture (VCF).

Virus: A small living particle that can infect cells and change how the cells function. The disease and the symptoms caused by a viral infection vary based on the type of virus and the type of cells that are infected.

W

Waldenström macroglobulinemia (WM): A rare type of non-Hodgkin’s lymphoma (NHL) that affects plasma cells. WM is not myeloma.

White blood cells (WBC): General term for a variety of leukocytes responsible for fighting invading germs, infections, and allergy-causing agents. These cells begin their development in bone marrow and then travel to other parts of the body. Specific white blood cells include neutrophils, basophils, eosinophils, lymphocytes, and monocytes.

X-ray: A form of electromagnetic radiation that can penetrate the human body. Used in low doses, X-rays produce images of structures and tissues inside the body that can reveal signs of disease or injury. In myeloma, a full skeletal survey using a series of X-rays is needed to show loss (osteoporosis) or thinning (osteopenia) of bone caused by myeloma bone destruction, lytic lesions, or any fracture or collapse of bone. X-rays show characteristic myeloma bone disease in a majority of patients, but X-rays are negative in approximately 25% of patients with active myeloma.

In closing

This booklet is not meant to replace the advice of your doctors and nurses who are best able to answer questions about your specific healthcare management plan. The IMF intends only to provide you with information that will guide you in discussions with your healthcare team.

To help ensure a good quality of life through effective treatment, you must have an active role in your own medical care. We encourage you to visit myeloma.org for more information and to join the IMF Myeloma Knowledge Platform at myprofile.myeloma.org.

To receive the most up-to-date information about myeloma in a caring and compassionate manner, call the IMF InfoLine at 1.818.487.7455, email InfoLine@myeloma.org, or visit mmsm.link/infoline to schedule a convenient time to talk with an IMF InfoLine Coordinator.

To get answers to your questions without having to wait, ask Myelo® anytime 24/7 at myeloma.org. This generative AI assistant is designed to help you find the right resources.

Use the hyperlinks and web addresses included in this publication for quick access to a variety of resources. Sign up at subscribe.myeloma.org for our quarterly journal Myeloma Today and weekly e-newsletter Myeloma Minute, as well as alerts about IMF news, events, and actions.

Selected acronyms and abbreviations

ADC: See Antibody-drug conjugate (ADC) page 6

Allo, allogeneic: Allogeneic (allograft) transplant –see Transplant (transplantation) page 40

ASCT, Auto: Autologous stem cell transplant –see Transplant (transplantation) page 40

β2M, β2M: See Beta-2 microglobulin (β2-microglobulin, β2M, or β2M) page 8

BCMA: See B-cell maturation antigen (BCMA) page 8

CAR T: See Chimeric antigen receptor (CAR) T-cell therapy page 11

CAT: See Computed axial tomography (CAT or CT) page 14

CBC: See Complete blood count (CBC) page 13

CELMoD: See Cereblon E3 ligase modulatory drug (CELMoD) page 11

CR: Complete response – see Response or remission page 35

CRP: See C-reactive protein (CRP) page 10

CRS: See Cytokine release syndrome (CRS) page 15

CT: See Computed axial tomography (CAT or CT) page 14

DLT: See Dose-limiting toxicity (DLT) page 16

DoR: See Duration of response (DoR) page 16

DpR: See Depth of response (DpR) page 15

DVT: See Deep vein thrombosis (DVT) page 15

ECOG status: Eastern Cooperative Oncology Group status –see Performance status page 32

EMD: See Extramedullary disease (EMD) page 17

FISH: See Fluorescence in situ hybridization (FISH) page 18

FLC: See Free light chain (FLC) page 18

GVHD: See Graft-versus-host disease (GVDH) page 19, and Transplant (transplantation) page 40

HDT: High-dose therapy – see Transplant (transplantation) page 40

HR: High-risk – see High-risk multiple myeloma (HRMM) page 20

IFE: See Immunofixation electrophoresis (IFE) page 22

Ig: See Immunoglobulin (Ig) page 22

IV: See Intravenous (IV) infusion page 24

IVIG: See Intravenous immunoglobulin (IVIG) page 24

MGUS: See Monoclonal gammopathy of undetermined significance (MGUS) page 27

MR: Minimal response – see Response or remission page 35

MRD: See Minimal residual disease (MRD) page 27

MRI: See Magnetic resonance imaging (MRI) page 26

mSMART: Mayo Stratification of Myeloma and Risk-Adapted Therapy

MTD: See Maximum-tolerated dose (MTD) page 26

NA, N/A: Not applicable

NDMM: Newly diagnosed multiple myeloma

NGF: See Next-generation flow page 29

NGS: See Next-generation sequencing (NGS) page 29

NR: Not reached

ONJ: See Osteonecrosis of the jaw (ONJ) page 31

ORR: See Overall response rate (ORR) page 31

OS: See Overall survival (OS) page 31

PCLI: Plasma cell labeling index

PCR: Polymerase chain reaction (test)

PET: See Positron emission tomography (PET) page 33

PFS: See Progression-free survival (PFS) page 33

PN: See Peripheral neuropathy (PN) page 29

PR: Partial response – see Response or remission page 35

RQPCR: Real-time quantitative polymerase chain reaction (DNA test)

RRMM: Relapsed/refractory multiple myeloma page 35

R-ISS: Revised International Staging System – see Staging page 38

REMS: See Risk evaluation and mitigation strategy (REMS) page 35

sCR: Stringent complete response – see Response or remission page 35

SD: See Stable disease (SD) page 38

SINE: See Selective inhibitor of nuclear export (SINE) page 36

SMM: See Smoldering multiple myeloma (SMM) page 37

SPM: See Second primary malignancy (SPM) page 36

SQ: See Subcutaneous (SQ) injection page 39

SRE: See Skeletal-related event (SRE) page 37

TTP: See Time-to-progression (TTP) page 40

VCF: See Vertebral compression fracture (VCF) page 42

VEGF: See Vascular endothelial growth factor (VEGF) page 42

VGPR: Very good partial response – see Response or remission page 35

Founded in 1990, the International Myeloma Foundation (IMF) is the world’s leading organization dedicated to multiple myeloma. The IMF is steadfast in its mission: Accelerating the prevention and cure of myeloma and improving the quality of life for patients and families.

The IMF serves people impacted by myeloma at every stage of the disease by combining world-class research, trusted education, global advocacy, and direct support. A cornerstone of this work is the International Myeloma Working Group® (IMWG) – a network of more than 300 internationally renowned researchers and clinicians who establish the guidelines that shape how myeloma is diagnosed, treated, and managed across the globe.

Through its global network of support groups, educational programs, its 24/7 generative-AI myeloma assistant Myelo® , its InfoLine staff, and its advocacy for greater healthcare access, the IMF helps people living with myeloma and their care partners navigate diagnosis, treatment, and survivorship. At the same time, the IMF ensures scientific advances translate into better care and outcomes.

Myeloma Glossary

Understanding Myeloma Vocabulary

You are not alone

The IMF InfoLine

IMF publications

What you will learn from this booklet

Myeloma-related terms from A to Z A

B

E

G

K

L

O

V

W

In closing

Selected acronyms and abbreviations