%0 Journal Article
%T Detection of Minimal Residual Disease by Flow Cytometry for Patients with Multiple Myeloma Submitted to Autologous Hematopoietic Stem Cell Transplantation
%A Suzane Dal B¨®
%A Annelise Pezzi
%A Bruna Amorin
%A Vanessa Valim
%A Rosane Isabel Bittencourt
%A Lucia Silla
%J ISRN Hematology
%D 2013
%R 10.1155/2013/847672
%X The treatment strategy in multiple myeloma (MM) is to get complete remission followed by high-dose chemotherapy and autologous Hematopoietic Stem Cell Transplantation (HSCT). Neoplastic Plasma Cells (NPCs) are , , CD138+, CD19£¿, and£¿£¿ in most cases. The description of this immunophenotype is of major importance as it leads to the correct identification of minimal residual disease (MRD). Samples from 44 Patients were analyzed prospectively in this study. We analyzed if the presence of MRD at three months after HSCT was predictive of relapse or death. There were 40 evaluable patients of whom 16/40 patients had MRD at three moths after HSCT and there were none in cytological relapse. The mean overall survival (OS) was 34 months and disease-free survival (RFS) was 28 months after HSCT. There was no significant difference in the log rank analysis comparing OS and the presence of MRD ( ) and RFS ( ). Here, we demonstrate that three color flow cytometry (FCM) is more sensitive for MDR evaluation than cytological analyzes. However, based in our data we can not affirm that MRD is a good predictor of MM relapse or death. In conclusion, our results could be attributed to a short followup, small sample size, and over most to the inability of a three-color FCM to detect the NPC population. 1. Introduction Multiple myeloma (MM) is a malignant disease characterized by an increase in the number of clonal plasma cells in the bone marrow (BM) and the presence of monoclonal protein, the M-protein, usually IgG or IgA, in blood, urine, or both [1]. Clinical signs are different combinations of bone marrow plasma cell infiltration with or without impaired hematopoiesis [2]; production of monoclonal immunoglobulin with decrease in the production of normal, polyclonal gammaglobulins; osteolytic lesions [3, 4], hypercalcemia, and renal failure. Since the clinical picture is heterogeneous, diagnostic criteria are mandatory in routine clinical practice being the Durie and Salmon staging criteria the gold standard to diagnose and stage MM. These criteria combine hemoglobin 2£¿g/dL below the normal level for the laboratory or if the haemoglobin falls to 10£¿g/dL, a serum calcium level >0.25£¿mmol/L, the serum creatinine >173£¿mmol/L, M-protein in serum >30£¿g/L, and bone involvement [5, 6]. A finding of 10% or more plasma cells in bone marrow aspirate (BMA) is one of the three major criteria for the diagnosis of MM. For risk stratification, apart from the Durie and Salmon criteria, the International Myeloma Foundation has recently recommended the International Staging System (ISS), a new
%U http://www.hindawi.com/journals/isrn.hematology/2013/847672/