Immunophenotyping in multiple myeloma and related plasma cell disorders

Abstract

SUMMARYPlasma cell disorders form a spectrum ranging from the asymptomatic presence of small monoclonal populations of plasma cells to conditions like plasma cell leukemia and multiple myeloma, in which the bone marrow can be replaced by the accumulation of neoplastic plasma cells. Immunophenotyping has become an invaluable tool in the management of hematological malignancies and is increasingly finding a role in the diagnosis and monitoring of plasma cell disorders. Multiparameter flow cytometry has evolved considerably during the past decade with an increasing ability to screen large numbers of events and to detect multiple antigens at the same time. This, along with a better understanding of the phenotypic heterogeneity of the clonal plasma cells in different disorders, has made immunophenotyping an indispensible tool in the diagnosis, prognostic classification and management of plasma cell disorders. This book chapter addresses the approaches taken to evaluate monoclonal plasma cell disorders, and the different markers and techniques that are important for the study of these diseases.

Revised Prognostic Staging System for Light Chain Amyloidosis Incorporating Cardiac Biomarkers and Serum Free Light Chain Measurements

“…Presence of circulating plasma cells was determined using flow cytometry using antibodies to surface CD138 and CD38. 22 Plasma cell labeling index (PCLI) is a measure of plasma cell proliferation and was determined via a slide-based assay that uses bromodeoxy uridine uptake by the dividing plasma cells, as described before. 23 …”

Robust isolation of malignant plasma cells in multiple myeloma

“…6 Nevertheless, the CD138 antigen has an important drawback in that it disappears rapidly from the cell surface when the analysis is delayed or when the sample is frozen. 4,7 This phenomenon, attributed to rapid molecular turnover and shedding, 8 limits the tolerable time between sampling and analysis, and reduces sensitivity. 7 Although CD138 is applicable to freshly collected samples, robust MMPC markers would facilitate molecular MM diagnostics.…”

Plasma Cell Immunophenotyping Improve Prognostic Stratification of Multiple Myeloma Patients

“…CD20 antigen expression has been associated with small mature plasma cell morphology and the occurrence of t (11;14) in lymphomas (35). Given the success of anti-CD20 directed monoclonal anti-body therapy in lymphoma, trials have been carried out with Rituximab in myeloma, but without any clear efficacy, suggesting little hope for a positive prognosis (1). Unfortunately, our study did not confirm the prognostic value of the CD117 antigen (36).…”

“…Patients with MGUS included 11 men and 6 women (median age: 65 years). MM patient characteristics are summarized in Table 1. At the time of final analysis, 18 patients (16%) had died.…”

“…The technological development of multi-parametric flow cytometry (MFC), in addition to the availability of anti-bodies to detect specific antigens, has provided insights into pathophysiology comprehension (1)(2)(3) and advanced the uses of MFC in clinical practice (4)(5)(6)(7)(8)(9)(10)(11)(12). Its main applications in relation to monoclonal gammopathies are diagnosis and differential diagnosis (7,13,14), evaluation of risk progression in MGUS and asymptomatic MM (aMM) (9), detection of minimal residual disease (MRD) in MM-treated patients (15,16), and identification of patients with poor prognosis (10,17).…”