Detection of Bcl-2/IgH Rearrangements by Quantitative-competitive PCR and Capillary Electrophoresis

Background: PCR is the primary method for detecting minimal residual disease in hematologic cancers. One such gene target is the bcl-2/immunoglobulin heavy chain (IgH) translocation found in a majority of cases of follicular lymphoma.

Methods And Results: We report an accurate method for quantitative detection of the bcl-2/IgH translocation marker of follicular lymphoma in a series of patients in various stages of remission and relapse who had been treated with a combination of ifosfamide, mitoxantrone, and etoposide (MINE) chemotherapy and monoclonal anti-CD20 antibody (Rituximab). The approach uses seminested PCR followed by analysis of the products on a fluorescent capillary electrophoresis system. The quantitation of bcl-2/IgH translocation-positive cells was sensitive and reproducible, capable of detecting as few as five malignant cells out of 300,000 normal cells.

Conclusion: Quantitative PCR enables one to monitor the kinetics of tumor reduction in patients treated with MINE chemotherapy in combination with Rituximab.