Multiparameter Flow Cytometry Immunophenotyping for the Identification of Smoldering Multiple Myeloma: A Case Report

Smoldering multiple myeloma (SMM) is a clonal plasma cell (PC) condition that falls between monoclonal gammopathy of unknown significance (MGUS) and multiple myeloma (MM). Detecting SMM patients allows for early therapy, which slows the disease's course and reduces morbidity. This report illustrates the case of a 68-year-old male who presented with suspected plasma cell dyscrasia. Multiparameter flow cytometry (MFC) immunophenotypic characteristics of bone marrow, absence of cytogenetic abnormalities (low risk) with no evidence of CRAB features (hypercalcemia, renal insufficiency, anemia, bone lesion), confirmed the diagnosis of smoldering multiple myeloma as evidenced by increased plasma cells (both mature and immature) comprising 70% of NEC of bone marrow revealed by bone marrow study, monoclonal [(“M”) spike band value of 5.71gm/dl] seen in Gamma region by serum protein electrophoresis and monoclonal gammopathy with IgG band and Kappa band by immunofixation. MFC's involvement in analysing neoplastic PCs is becoming increasingly important in precisely identifying and quantifying BMPCs with malignant potential from normal PCs, assisting in the diagnosis and classification of Plasma cell dyscrasias.