Plasma Cell Dyscrasias

Plasma cell dyscrasias are diseases of the hematologic system, the most common of which is multiple myeloma. Multiple myeloma can evolve from a premalignant monoclonal gammopathy. Monoclonal gammopathy of undetermined significance (MGUS) is present in 3-4% of adults older than 50 years and is characterized by low levels of monoclonal protein, low bone marrow involvement, and the absence of end-organ damage. Once a certain monoclonal protein threshold is reached, the disease is defined as smoldering multiple myeloma (SMM), and once end-organ damage appears, the gammopathy has progressed to multiple myeloma. 

Plasma cell dyscrasia evaluation begins with an investigation of the presence and type of monoclonal proteins (also known as M proteins). Serum free light chain (SFLC) quantification aids in diagnosing multiple myeloma and determining prognosis.  Bone marrow evaluation is essential for diagnosis.  Further testing can include multiparameter flow cytometry and plasma cell fluorescence in situ hybridization (FISH) to determine prognosis and cytogenetic studies to identify high-risk variants. 

Tabs Content
Content Review: 
October 2019

Last Update: January 2020