Related Diseases

Myeloma shares some similar features and symptoms with other blood disorders, including:

Monoclonal gammopathy
Waldenström macroglobulinemia (WM)
Primary amyloidosis
Heavy chain disease
Light chain deposition disease (LCDD)
Plasma cell leukemia (PCL)
POEMS syndrome

Monoclonal Gammopathy

This condition, also called “benign monoclonal gammopathy,” is present in 3 to 4 percent of the general population older than 50 years. Monoclonal gammopathy of undetermined significance is associated with monoclonal protein in the blood, but the condition does not present any symptoms or affect the well-being of the patient, and it is usually found as an incidental finding of routine laboratory tests. Only 10 percent of patients with newly-diagnosed myeloma have a history of MGUS, and its associated risk of progression to myeloma is approximately 1 percent per year. Patients are usually monitored with blood tests once or twice a year to determine if there is any change in the level of monoclonal protein. For more information see the free LLS fact sheet, Monoclonal Gammopathy of Undetermined Significance (MGUS) Facts.

Waldenström Macroglobulinemia (WM)

This disease has some features in common with myeloma. It is a malignancy of B lymphocytes that produce a monoclonal immunoglobulin that can be measured in the blood. The malignant B lymphocytes replace the normal marrow cells and may cause anemia and other blood cell deficiencies by preventing the normal marrow cells from making blood cells efficiently. The monoclonal (M) immunoglobulin produced by the malignant B lymphocyte is a very large type of immunoglobulin M (IgM), referred to as a “macroglobulin” (large globulin). For more information see the free LLS fact sheet, Waldenström Macroglobulinemia Facts.

Primary Amyloidosis

This is an uncommon disease process associated with the accumulation of “amyloid” in tissues, such as the heart, the gastrointestinal tract, the nerves or the skin. Although there are several types of amyloid, one type is associated with a condition known as “amyloid light-chain (AL) amyloidosis,” which is caused by the deposit of damaged immunoglobulin light chains. In some patients with myeloma, the light chains made by plasma cells can result in the formation and deposition (buildup) of amyloid. This type of amyloidosis can occur either with or without overt myeloma and is called “primary amyloidosis.” In myeloma patients who have primary amyloidosis, involvement of the heart, intestines or nerves can produce dysfunction in those organs, significantly complicating management of the disease.

In patients who have primary amyloidosis without myeloma, the number of plasma cells in the marrow may not be increased and the bones may not be affected. In these cases, the malignant B lymphocytes producing the light chains that build up in the tissues and form the amyloid are too few to be detected by a bone marrow biopsy. Diagnosis of amyloidosis relies on some of the same tests used to diagnose myeloma; however, occasionally it is necessary to perform biopsies of other sites, such as the abdominal fat pad, gums, colon, heart or kidneys. Staging is determined based on the results of blood tests that indicate heart function, including tests to measure N-terminal pro-brain natriuretic peptide (NT-proBNP) and either the troponin T or troponin I level. Many of the drugs that work against myeloma are also effective against amyloidosis, including corticosteroids, melphalan, bortezomib (Velcade®) and daratumumab (Darzalex®), while lenalidomide (Revlimid®) should be used with caution. In patients who are good candidates, autologous stem cell transplantation is the treatment of choice. For more information see the free LLS fact sheet, Amyloidosis Facts.

For information about the drugs listed on this page, visit Drug Listings.

Heavy Chain Disease

These are a family of rare, systemic syndromes involving B lymphocytes. They are called heavy chain diseases because the protein made by the malignant lymphocytes is an incomplete immunoglobulin (the heavy chain of the immunoglobulin). A heavy chain disease is similar to myeloma in that it is a malignancy of B lymphocytes that secrete a characteristic immunoglobulin, but its clinical features are quite different. For example, there is no bone disease. Treatment generally involves chemotherapy, corticosteroids and, in some cases, radiation therapy.

Light Chain Deposition Disease (LCDD)

A systemic disorder that involves the immune system, LCDD is caused by an excess buildup of immunoglobulin light chains in the tissues and organs. Light chains are an important part of the body's immune system. However, if they become trapped in the tissues of the kidneys, lungs, skin, joints or blood vessels, the light chains can set off reactions leading to tissue or organ inflammation and damage. Early signs and symptoms of light chain deposition disease may include protein in the urine, high blood pressure, decreased kidney function and nephrotic syndrome (a kidney disorder that causes the body to lose too much protein in the urine). LCDD can occur in patients who have myeloma as well as in individuals who have monoclonal gammopathy of undetermined significance (MGUS) or lymph node disorders.

Plasma Cell Leukemia (PCL)

A rare plasma cell disease that may be primary (without known cause) or secondary (evolving from an existing diagnosis of myeloma). Most cases are primary; approximately 5 percent of cases are diagnosed in patients who have myeloma. In this disorder, patients have high numbers of plasma cells (greater than 20 percent) circulating in the blood, often creating plasmacytomas throughout the body. This disease is treated like myeloma but frequently requires more aggressive therapy as this disease is more aggressive than myeloma.

POEMS Syndrome

POEMS syndrome is an uncommon marrow disorder related to myeloma. It gets its name from its five most common features: peripheral neuropathy (P), organ enlargement (O), endocrine gland dysfunction (E), monoclonal plasma cell tumors and monoclonal immunoglobulin (M) and skin changes (S). Peripheral neuropathy is often the most disabling feature of the syndrome and can include progressive weakness of the arms or legs. Liver or spleen enlargement is less common. The bone alterations related to the accumulation of plasma cells in the marrow are different from bone alterations in classic myeloma (the marrow looks denser than normal, rather than less dense). Thyroid or sex hormone deficiencies caused by endocrine gland dysfunction may require hormone replacement therapy. Other features not included in the POEMS acronym are high red blood cell or platelet counts, extravascular volume overload (swelling) and lung disease. Patients can benefit from radiation or chemotherapy treatment and, in some cases, from autologous stem cell transplantation.