Plasma Cell Disorders

The plasma cell disorders are a heterogeneous group of clonal plasma cell proliferations with clinical presentations that range from a completely asymptomatic laboratory finding to a highly aggressive malignant neoplasm. The correct diagnosis and classification of these diseases requires correlation of the bone marrow morphologic findings with the clinical features and results of other laboratory tests. Increasingly, molecular cytogenetic characterization is also an important aspect of the workup of plasma cell disorders. This chapter summarizes the approach to the diagnosis and classification of the major plasma cell disorders including plasma cell myeloma, monoclonal gammopathy of undetermined significance, plasma cell leukemia, and primary amyloidosis.