Utility of Gene Scan for Detection of MRD in Precursor B-Cell Neoplasm.

Abstract 4720

Reliable Techniques are needed for detection of MRD to evaluate the effectiveness of the treatment in patients with precursor B-cell leukemia/lymphoma and to predict impending relapse prior to clinical manifestations. Currently, PCR analysis of Ag receptor gene rearrangements and flowcytometry (FC) represent the most clinically useful techniques for MRD analysis in ALL. In this study, we assessed the applicability of a non–sequence based PCR technique for the detection of MRD namely gene scan (GS) as compared to multicolor FC and real time quantitative PCR (RQ PCR). As a pilot study, results of MRD using the three techniques were assessed in 8 follow-up bone marrow samples of patients with precursor B-Cell leukemia/lymphoma. MRD detection using fluorescent GS was positive in 87.5% of samples compared to 37.5% using four colour FC. RQ-PCR was applied on 4 samples using patient-specific allele-specific oligonucleotide and revealed the presence of MRD in all of them. Only 3 of those sample gave positive result for MRD using both 4-colour FC and GS. Fluorescent GS technique as a known simple, rapid, and cost effective method might be a reliable technique for detection of MRD in precursor B-Cell leukemia/lymphoma as it showed a considerable sensitivity compared to four colour FC. However, a large-scale study for accurate assessment of sensitivity and specificity of Fluorescent GS in comparison with RQ-PCR as a gold standard technique is now undergoing.