What is Multiple Myeloma?
Multiple myeloma is a cancer of a type of white blood cell called a plasma cell. Plasma cells live in your bone marrow and make proteins that help your immune system fight infection.
Bone marrow produces:
- Red blood cells that carry oxygen
- White blood cells, which are part of your immune system
- Platelets that help the blood clot
With multiple myeloma, your plasma cells grow out of control (become cancerous) and crowd your bone marrow. As a result, your bone marrow cannot produce enough of these healthy cells. These cancerous cells are called myeloma cells.
You become anemic with fewer red blood cells and may get life-threatening infections. With fewer platelets, you may bruise or bleed easier. All of these problems can affect your quality of life.
Myeloma cells produce abnormal proteins called monoclonal or M-proteins. These proteins make it hard for your kidneys to clean your blood and can lead to kidney problems.
Myeloma cells also damage cells that keep your bones healthy by keeping them from rebuilding. This can lead to bone loss and fractures that don't heal. As your bones degenerate, they release calcium into your blood, which causes fatigue, constipation, and confusion.
Myeloma can also form a solid tumor called a solitary plasmacytoma rather than infect your entire bone marrow. These tumors are often treated with radiation therapy.
The American Cancer Society estimates that about 32,000 people in the U.S. will be diagnosed with multiple myeloma this year.
Stages of Multiple Myeloma
Physicians consult two main systems when determining the stage of a patient's multiple myeloma:
- The Revised International Staging System (R-ISS) is the more commonly used of the two. It relies on measures of a patient's B2-microglobulin and serum albumin, LDH (Lactate Dehydrogenase), and chromosomal testing (Cytogenetics). This system categorizes myeloma as Stage I, II, or III. Patients' prognosis, or overall survival, decreases as the stage rises.
- The Durie-Salmon Staging System is older and less widely used than the ISS. Stages are also divided into Stages I, II, and III. Still, the stages of multiple myeloma are determined by several factors, including blood calcium levels, hemoglobin value, levels of M-protein in blood or urine, and the amount of myeloma cells in the body.
Types of Multiple Myeloma
Monoclonal gammopathy of unknown significance
Some cases of multiple myeloma are classified as premalignant clonal plasma cell disorders. Disorders included in this category are called MGUS (monoclonal gammopathy of unknown significance) and smoldering multiple myeloma. In most patients, these disorders are asymptomatic and do not require treatment. However, these disorders can lead to complications in some patients, including peripheral neuropathy and renal disorders called monoclonal gammopathy of renal significance (MGRS).
Our colleagues in Columbia University Renal Pathology have been leaders in describing and characterizing the renal disorders associated with MGUS and are a major referral center for renal biopsies done in the U.S. At NewYork-Presbyterian, we collaborate closely with nephrologists and renal pathologists to develop individually tailored and cutting-edge strategies to treat these disorders.
Several other types of multiple myeloma can fall into either the smoldering or active type:
- Light chain myeloma - About a fifth of myeloma cases are light chain myeloma. Patients with this type of multiple myeloma do not create whole immunoglobin antibodies like those with other types of myeloma. They can only create incomplete or "light chain" antibodies.
- Nonsecretory myeloma - Patients with this type of myeloma do not create enough M-proteins or light chains for tests to detect. Imaging scans and bone marrow biopsies can help diagnose this form of the disease.
- Solitary Plasmacytoma - A single, localized tumor characterizes this rare form of myeloma called a plasmacytoma. This is unlike other "multiple" myelomas, which cause more than one tumor in different locations.
Signs & Symptoms of Multiple Myeloma
Many multiple myeloma patients may not notice symptoms early in the disease's progression. When multiple myeloma symptoms do occur, they vary widely but can include:
- Unexplained weight loss
- Excessive thirst
- Confusion or mental fogginess
- Bone pain, especially in the back, ribs, and skull
- Frequent infections
Causes & Risk Factors
Researchers still don't know what causes multiple myeloma. They do know, however, that certain risk factors can increase your chances of developing the disease. Things that affect your risk of developing multiple myeloma include:
- Age - The chances of developing multiple myeloma increase as a person ages. Most cases of the disease are diagnosed in people aged 65 and up
- Sex - Men are slightly more likely to develop myeloma than women
- Race - Multiple myeloma is more than twice as common in African Americans than in white patients
- Weight - Being overweight or obese increases a person's risk of developing myeloma
- Family history - A person is more likely to develop multiple myeloma if an immediate family member has the disease
- History of MGUS or smoldering myeloma - Patients with a known history of MGUS or smoldering myeloma are at risk of progression to symptomatic multiple myeloma at a rate of about 1% per year for patients with MGUS and about 10% per year for patients with smoldering multiple myeloma
Trust NewYork-Presbyterian for Multiple Myeloma Treatment
At NewYork-Presbyterian, we recognize that there are many types of multiple myeloma, each with its own biology. Our specialists are trained to screen for and recognize the signs of myeloma and can help guide you through the appropriate next steps.