Table of Contents
ISRN Hematology
Volume 2013, Article ID 847672, 7 pages
http://dx.doi.org/10.1155/2013/847672
Research Article

Detection of Minimal Residual Disease by Flow Cytometry for Patients with Multiple Myeloma Submitted to Autologous Hematopoietic Stem Cell Transplantation

1Unit of Hematology, Clinical Pathology Service, Hospital de Clínicas de Porto Alegre, 90035-903 Porto Alegre, RS, Brazil
2Laboratory of Cell Culture and Molecular Analysis of Hematopoietic Cells, Hospital de Clínicas de Porto Alegre, 90035-903 Porto Alegre, RS, Brazil
3Hematology and Bone Marrow Transplantation, Hospital de Clínicas de Porto Alegre, 90035-903 Porto Alegre, RS, Brazil

Received 29 April 2013; Accepted 29 May 2013

Academic Editors: A. Bosly and A. Gatt

Copyright © 2013 Suzane Dal Bó et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

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.