Types of multiple myeloma
There are different types of multiple myeloma, which are also considered stages:
- MGUS (monoclonal gammopathy of uncertain significance): It is characterized by the presence of an abnormal protein produced by the abnormal cells in the blood marrow and then released to the blood. The protein is known as protein M, but it is also known as paraprotein or myeloma protein.
- SMM (smoldering multiple myeloma): This is an intermediate stage between MGUS and active multiple myeloma. Patients will also have protein M, but the levels of this protein are higher. Another feature is the number of abnormal cells in the bone marrow, which is much higher than MGUS. Still, the patient remains asymptomatic.
- Solitary plasmacytoma: This one is similar to SMM because it is an intermediate stage between MGUS and active myeloma. The difference is that in solitary plasmacytoma, an actual mass or tumor of abnormal cells is clearly visible and growing in the vertebrae.
- Symptomatic or active multiple myeloma: When SMM or solitary plasmacytoma turns into the actual disease, we call it symptomatic or active multiple myeloma.
