Glossary of Multiple Myeloma Terms

If you've been diagnosed with multiple myeloma, your doctor may toss around medical terms that sound like a foreign language to you. But it's important not to shrug them off as part of their world, not yours.

The words could include important tests or treatments that play a role in the way you manage your disease. So spend a few minutes to learn the meaning of key terms that may crop up during your next appointment.

Albumin: A protein your liver makes that prevents fluid from leaking out of your blood vessels. Doctors measure the amount of albumin in blood to learn the stage of multiple myeloma.

Allogeneic stem cell transplant: Your bone marrow has stem cells that grow into blood cells. When you get chemotherapy to treat multiple myeloma, it kills healthy stem cells along with cancer cells. An allogeneic stem cell transplant replaces those destroyed stem cells with healthy blood-forming stem cells from a donor.

Amyloidosis: A disease in which an abnormal protein called amyloid builds up in organs like the kidneys, heart, or liver. Amyloid can affect how well these organs work. People often have both amyloidosis and multiple myeloma.

Anemia: It's one of the symptoms of multiple myeloma. It happens when too few red blood cells are in your body. Red blood cells carry oxygen to organs and tissues. Anemia can cause fatigue, weakness, and trouble breathing.

Autologous stem cell transplant: This treatment replaces stem cells destroyed during chemotherapy. Your doctor takes stem cells from your own bone marrow or blood before you get the chemo, and then injects them back into your vein afterward.

Beta-2 microglobulin (B2M) test: B2M is a protein that multiple myeloma cells make. The B2M test can show doctors how fast your cancer is growing and whether your treatment is working.

Blood urea nitrogen (BUN) test: A BUN test measures the amount of urea, a waste product, that's in your blood. A high BUN level may be a sign that your kidneys aren't working right.

Bone lesion: This is damage to your bones caused by multiple myeloma cells. Weakened bones hurt and can break easily.


Bone marrow aspiration/biopsy: These tests help diagnose multiple myeloma. Bone marrow aspiration removes a small amount of liquid from inside your bones. A biopsy removes a tiny piece of bone and marrow. Your doctor sends the sample to a lab that checks if cancer cells are in the bone marrow.

Creatinine: A waste product formed from the breakdown of muscle tissue. High creatinine levels in the blood are a signal that your kidneys aren't working well. About 50% of people with multiple myeloma have high creatinine levels.

Electrophoresis: This test separates proteins in the blood. It identifies abnormal proteins called monoclonal immunoglobulins to help diagnose multiple myeloma.

Erythropoietin (EPO): A hormone your kidneys make that helps your body make new red blood cells. It's used as a treatment for anemia, which can be a complication of multiple myeloma.

Human leukocyte antigen (HLA): HLA is a substance found on most cells in the body. It helps the immune system -- your body's defense against germs -- tell the difference between its own cells and foreign cells. A technique called HLA typing matches you with donors before a bone marrow transplant.

Hypercalcemia: It means you have high levels of calcium in your blood. Damage to your bones from multiple myeloma releases this mineral into the blood.

IgG kappa/IgG lambda: These terms classify the type of myeloma you may have. IgG kappa and IgG lambda are two kinds of immunoglobulins -- antibodies that myeloma cells make.

Immunofixation electrophoresis (IFE): A test used to diagnose multiple myeloma. Electrophoresis separates proteins in your blood. It helps identify abnormal antibodies called immunoglobulins.

Immunoglobulin: A type of antibody in the blood. Antibodies are proteins that help the immune system fight bacteria, viruses, and other germs. Multiple myeloma cells make abnormal immunoglobulins that can't fight infections.

Induction therapy: The first step in multiple myeloma treatment. Its goal is to cut down the number of myeloma cells in your bone marrow.

Kappa/lambda ratio: Kappa and lambda are two types of proteins that make up part of immunoglobulins. Measuring the kappa/lambda ratio can show whether your multiple myeloma is likely to get worse and if treatment is working.


Light chains: Parts of immunoglobulin, a type of antibody that multiple myeloma cells make. There are two kinds of light chains: kappa and gamma.

Lymphoma: A type of cancer that starts in the lymphatic system, the network of vessels that store and carry infection-fighting white blood cells. There are two kinds of lymphoma: Hodgkin's and non-Hodgkin's.

Lytic lesion: An area of damage to a bone that's caused by cancer.

Metastasis: Cancer that spreads from the place where it started to other parts of your body. When cancer spreads, doctors say it has "metastasized."

Monoclonal gammopathy of undetermined significance (MGUS): If you have this condition, you have too much of an abnormal protein called M protein in your blood. MGUS sometimes develops into multiple myeloma.

M protein: An abnormal protein in the blood. It can be a sign of multiple myeloma.

M spike: Large amounts of an abnormal protein called M protein in the blood. It affects most people with multiple myeloma.

Multiple myeloma: A cancer that forms from plasma cells in your bone marrow. Plasma cells make proteins called antibodies that help the immune system fight infections. In multiple myeloma, plasma cells make abnormal proteins that can't do their job right.

Myelodysplastic syndrome (MDS): A type of cancer in which there are abnormal blood-forming cells in bone marrow. These cells don't grow into healthy red blood cells, white blood cells, and platelets.

Myelogenous/myeloid: A term that refers to cells made in bone marrow.

Myeloma: A cancer of the plasma cells, which are white blood cells that fight infection.

Neurotrophic tyrosine receptor kinase (NTRK): This gene provides instructions for development and survival of nerve cells. A defect in this gene can make treatment of multiple myeloma difficult to treat. 

Neutropenia: Too few neutrophils in your blood. Neutrophils are white blood cells that fight infections. Neutropenia can be a complication of multiple myeloma treatment.

Plasmacytoma: A tumor that forms when plasma cells turn cancerous and begin to multiply out of control. When several tumors form in bones, the condition is called multiple myeloma.


Relapsed Refractory Multiple Myeloma (RRMM): This is when your cancer returns and is not responding to therapy. Fortunately, there are several treatment options available..

Scleroderma: An autoimmune disease that makes the skin hard, thick, and tight. In rare cases, it can affect people with multiple myeloma.

Serum protein electrophoresis: This test looks for certain proteins in the blood to diagnose multiple myeloma.

Smoldering myeloma: This is an increased level of abnormal M protein in your blood, but without multiple myeloma symptoms.

WebMD Medical Reference Reviewed by Neha Pathak, MD on December 09, 2020



AACC: "Protein Electrophoresis/Immunofixation Electrophoresis," "Serum Free Light Chains."

American Cancer Society: "Multiple Myeloma Stages," "Stem Cell Transplant for Multiple Myeloma," "Tests to Find Multiple Myeloma," "What are Myelodysplastic Syndromes?"

American Society of Hematology: "Myeloma."

Be The Match: "HLA Basics."

BMJ Case Reports: "Coexistence of scleroderma with multiple myeloma: A rare association."

Canadian Cancer Society: "Induction Therapy for Multiple Myeloma."

Cancer.Net: "What is Metastasis?"

Cancer Research UK: "Types of myeloma."

Leukemia & Lymphoma Society: "Understanding Multiple Myeloma and Laboratory Values."

Mayo Clinic: "Anemia: Symptoms & Causes," "Multiple myeloma: Overview," "Neutropenia," "Scleroderma: Symptoms & causes."

Memorial Sloan Kettering Cancer Center: "Systemic Amyloidoses."

Multiple Myeloma Research Foundation: "Beta-2 Microglobulin Test," "Blood Chemistry Tests," "Bone Lesions and Damage," "Complication: Anemia," "Hypercalcemia," "MGUS and Multiple Myeloma," "Plasmacytoma," "Smoldering Multiple Myeloma," "Stem Cell Transplants," "Types of Immunoglobulins in Multiple Myeloma," "What is Electrophoresis?" "What is Erythropoietin?" "What is Revlimid?"

Myeloma Crowd: "Deciphering My Myeloma Test Results," "Myeloma 101: What is neutropenia and what does it mean to the myeloma patient?" "Types of Multiple Myeloma."

National Cancer Institute: "Human Leukocyte Antigen," "Lytic Lesion," "Myelogenous."

OncoLink: "About Multiple Myeloma."

Stanford Health Care: "AL (Primary) Amyloidosis."

Sylvester Comprehensive Cancer Center: "Definition: Leukemia, Lymphoma, and Myeloma."

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