plasma cell leukemia

Plasma cell leukemia (PCL) is a rare form of plasma cell dyscrasia and is classified into two clinical types.

The primary type occurs in individuals without being preceded by multiple myeloma, whereas the secondary type is a rare complication of the late-stage multiple myeloma.

In certain PCL cases, the leukemic cells are more immature than usual and a definitive diagnosis is difficult to obtain without electron microscopic or immunohistochemical studies.

A plasma cell leukemia can contain the lambda-type Bence–Jones protein.

The tumor cells in the peripheral blood can be small lymphoid or lymphoplasmacytoid cells with numerous cytoplasmic hairy projections.

These cells can not show any of the characteristics of mature plasma cells and their plasma cell nature can be difficult to identify using conventional microscopic examinations.

Immunohistochemical staining with monoclonal antibodies is useful for establishing a diagnosis of plasma cell leukemia or multiple myeloma.

Kawano et al. claimed that immunohistochemical staining using monoclonal antibodies, such as CD38, VLA-5 and MPC-1, could also reveal the stage of maturation.

Furthermore, a molecular analysis of the immunoglobulin variable region now provides invaluable information on the status of tumors with a B-cell lineage, thus confirming the proper categorization of B-cell tumors at the molecular level.

To characterize the nature of the cell origin in this unique case of plasma cell leukemia, it is possible to analyze the immunoglobulin light chain (VL) and heavy chain (VH) gene loci of the leukemic cells.