Myeloma Bone Disease & Multiple Myeloma Causes and Symptoms
Myeloma bone disease or multiple myeloma is a cancer formed by a type of white blood cell called the plasma cell. Since the bone marrow is the site of formation of many blood cell types, it is a common site of involvement in multiple myeloma. Plasma cells are the population responsible for making antibodies. As the disease progresses, the cancerous cells produce large amounts of paraproteins, which cause many of the manifestations of multiple myeloma throughout the body.
Myeloma bone disease or multiple myeloma affects approximately 1-4 people out of every 100,000 and makes up approximately 1% of all cancers, making the disease the most common primary bone malignancy. It is rare to see this disease affect people under the age of 40. For unknown reasons, myeloma bone disease or multiple myeloma is more common in men. It also occurs twice as often in African Americans as it does Caucasians.
Anatomy of the Bone Marrow
Bone marrow is the spongy material inside the bones. There are two types – red and yellow. The yellow bone marrow consists of fatty tissue, while the red bone marrow consists of the following:
- Marrow Stem Cells
- Red blood cells
- White blood cells
Bones are complex, and inside each bone is bone marrow, which produces and stores blood cells that are important to the daily functioning of the body. When the bone marrow is compromised by myeloma bone disease or multiple myeloma, it can affect the bone structure, causing the bones to weaken.
Types of Myeloma Bone Disease and Multiple Myeloma
Myeloma bone disease and multiple myeloma can be divided into various stages, depending upon the progression of the disease:
- Solitary plasmacytoma – This is the condition in which a tumor is formed by malignant plasma cells, but no other malignant plasma cells are found elsewhere in the body.
- Monoclonal gammopathy of undetermined significance (MGUS) – Early in the disease spectrum, this condition demonstrates increased paraprotein levels and plasma cell proliferation. While widely considered a premalignant condition, there is a persistent risk of progression to symptomatic myeloma.
- Asymptomatic myeloma – While more advanced than MGUS, asymptomatic myeloma patients do not exhibit signs of organ damage from the disease.
- Symptomatic – This is the active form of myeloma bone disease and multiple myeloma and can lead to multiple tumors called plasmacytomas, which are formed by many cancerous cells. This type of myeloma is characterized by the presence of organ damage, most commonly to the bone.
Causes of Myeloma Bone Disease and Multiple Myeloma
Although the causes of myeloma bone disease and multiple myeloma are relatively unknown, there are several factors that increase a person’s risk for contracting that first cancerous plasma cell that can set the disease in motion:
- Genetic abnormalities – While the specifics about this are still being researched, it is known that every case of myeloma includes the patient experiencing at least some genetic abnormalities. These include defects in chromosomes 13, 14 and 17. Significant evidence suggests that the type of genetic alteration may have prognostic importance.
- MGUS – Monoclonal gammopathy of undeteremined significance is now recognized as a precursor to multiple myeloma. Though not all patients will progress to symptomatic myeloma, nearly all cases of symptomatic myeloma were preceded by MGUS.
Symptoms of Myeloma Bone Disease and Multiple Myeloma
Depending on the type of myeloma bone disease and multiple myeloma, symptoms vary. With the more aggressive forms of myeloma, the symptoms seen are fairly extensive.
The following are some of the most common myeloma bone disease and multiple myeloma symptoms. Every person is different, so not all of these symptoms may be present:
- Bone pain, especially in the ribs and back
- Bone fractures
- Weight loss
- Frequent infections
Myeloma bone disease and multiple myeloma symptoms are very similar to the symptoms of other medical conditions. Seek help from a doctor if you have any of these symptoms or think you may be at risk of having myeloma bone disease or multiple myeloma.
The multidisciplinary team of orthopaedic experts at North Shore-LIJ Orthopaedic Institute's musculoskeletal oncology services in New York treats myeloma bone disease/multiple myeloma as well as a broad range of conditions that affect the bones within the body.