Abstract and Introduction
Plasma cell leukemia (PCL) is a rare and aggressive plasma cell dyscrasia. Patients with PCL have a very poor prognosis with median survival measured in months. PCL can present de novo or following a prodrome of plasma cell myeloma. Patients with PCL tend to present with aggressive clinical features, such as extramedullary disease, bone marrow failure, advanced stage disease and expression of distinct immunophenotypic markers, such as lack of CD56 and presence of CD20. Historically, the treatment of PCL has primarily been palliative, with only a small minority of patients achieving a durable remission. The impact of newer agents, such as bortezomib and lenalidomide, in conjunction with autologous and allogeneic stem cell transplantation is uncertain, but emerging data suggest that use of these modalities may help improve the poor prognosis of patients with PCL.
The 2008 WHO classification recognizes plasma cell leukemia (PCL) as a rare and clinically aggressive variant of plasma cell myeloma, characterized by the expansion of a clone of immunoglobulin-secreting terminally differentiated mature B cells. PCL represents a minority of cases of plasma cell myeloma, accounting for 0.6–4% of all cases,[1,2] although the latter may represent the referral bias seen in single institution retrospective analyses. The diagnostic criteria for PCL include the presence of a circulating clonal plasma cell count of more than 2000/µl (if the total white blood cell count is >10,000/µl) or the presence of more than 20% circulating plasma cells. PCL can be secondary PCL (sPCL) if arising from a known diagnosis of plasma cell myeloma or primary PCL (pPCL) if no prior history of plasma cell myeloma can be ascertained. sPCL was felt to arise late in the course of plasma cell myeloma and those patients have been described to have a worse prognosis than those with pPCL. However, a recent report indicates that the median time to transformation to sPCL from plasma cell myeloma is approximately 21 months. The primary form accounts for 60% of all cases of PCL.
Expert Rev Hematol. 2010;3(5):543-549. © 2010 Expert Reviews Ltd.
Cite this: Plasma Cell Leukemia: Concepts and Management - Medscape - Oct 01, 2010.