What Is Multiple Myeloma?
In multiple myeloma, a type of white blood cell called a plasma cell multiplies unusually. Normally, they make antibodies that help fight infections. But in multiple myeloma, they release too much protein (called immunoglobulin) into the bones and blood. It builds up throughout the body, causing organ damage.
The plasma cells also crowd normal blood cells in the bone. They release chemicals that dissolve bone. The weak areas of bone created by this are called lytic lesions.
As multiple myeloma gets worse, those plasma cells begin to spill out of the bone marrow and spread through the body. This causes more organ damage.
No one knows what causes multiple myeloma. But certain things can raise your chances of having it:
- Being older than 65
- Being African-American
- Having a family member with it
People with these other plasma cell diseases are more likely to get multiple myeloma:
- Monoclonal gammopathy of undetermined significance (MGUS)
- Solitary plasmacytoma
Early on, multiple myeloma may cause no symptoms. As time passes, you may have:
In rare cases, plasma cells may form purplish lumps that you can see underneath the skin. Your doctor may call them “extramedullary plasmacytomas.”
Your doctor may test you for multiple myeloma if a blood test reveals:
- Too much calcium in your blood (your doctor may call it “hypercalcemia”)
- Anemia (too few red blood cells)
- Kidney problems
- High protein levels in your blood combined with a low albumin level (your doctor may say you have a "globulin gap")
If your doctor thinks you have multiple myeloma, he’ll test your blood, urine, and bones. Some tests he may order include:
- Electrophoresis, which measures immunoglobulins (something your body makes when it’s fighting something)
- Blood urea nitrogen, also known as BUN, and creatinine -- to check how well your kidneys are working
- A CBC, which stands for complete blood count, which measures and counts the cells in your blood
After your test results come in, your doctor may want you to have a bone marrow biopsy. He will insert a needle into a bone, usually in your hip, to get a sample of bone marrow to check the number of plasma cells in it.
Treating multiple myeloma usually helps people who already have:
- High blood calcium
- Kidney problems
- Lytic bone lesions
The most effective treatment for multiple myeloma is stem cell transplantation (SCT).
In SCT, some of your stem cells are removed by a machine, frozen, and stored. They may also be taken from a donor.
Next, you may have high-dose chemotherapy. This will destroy almost all the cells in the bone marrow -- both healthy cells and the plasma cells that cause the disease.
The stem cells are then injected into your veins. They travel to the bone marrow, where they multiply and make new, healthy blood cells.
Stem cell transplantation doesn't cure multiple myeloma, but it often helps you live longer.
It’s important for you to know that SCT can cause serious complications, including making you more prone to infections.
Chemotherapy alone doesn't usually work as well as stem cell transplantation for multiple myeloma treatment. But it’s often a good option for people at higher risk for complications from stem cell transplantation.
Doctors usually combine chemotherapy with other drugs to treat the disease. Treatment may include some of these drugs:
- Adriamycin, doxil (Doxorubicin)
- Bendamustine (Treanda)
- Bortezomib (Velcade)
- Carfilzomib (Kyprolis)
- Cyclophosphamide (Cytoxan)
- Ixazomib (Ninlaro)
- Lenalidomide (Revlimid)
- Melphalan (Alkeran)
- Pomalidomide (Pomalyst)
- Thalidomide (Thalomid)
- Vincristine (Oncovin)
Corticosteroids (like dexamethasone or prednisone) are often given with chemotherapy to reduce side effects. Interferon is a hormone-like drug that can help keep the condition in remission after chemo.
Bisphosphonates are drugs used to treat bone damage. Your doctor may suggest pamidronate (Aredia) and zoledronic acid (Zometa), which you'll get through a vein. Be especially good about your dental hygiene while taking these medications. There is a rare risk of deterioration of the jaw. That risk can increase if you get dental work.
Immunotherapy is a treatment that uses antibodies to attack the cancer cells. It is usually reserved for patients who have not had success with other treatments. Daratumumab (Darzalex) and elotuzumab (Empliciti) are two antibodies that target multiple myeloma cells.
Radiation therapy may also help you. A beam is directed from a machine to a bone or other affected part of the body. The rays kill plasma cells, helping to lessen pain and strengthen the weakened bone.
Research is ongoing, including clinical trials to identify more effective chemotherapy drugs and combinations.
What to Expect
Multiple myeloma varies widely between people. Some will live for years with few symptoms. With others, the condition gets worse quickly. Identifying the forms of multiple myeloma is often challenging for doctors.
Systems have been developed that predict survival rates. The simplest and most common uses the blood levels of two substances: albumin and beta-2-microglobulin. A higher albumin level and a lower beta-2-microglobulin level suggest a better chance for longer survival.
Other systems use multiple lab or DNA tests in plasma cells.
Knowing how aggressive your multiple myeloma is can help you and your doctor find the best plan for you.
What Your Doctor Is Reading
If you are interested in more advanced reading on this topic, we’ve made content from our health professional site, Medscape, available to you on WebMD.