Purpose: To determine the incidence and frequency of the Bcl-2/IgH rearrangement in the peripheral blood of normal individuals to define the potential complication this may pose for the molecular monitoring of disease in patients with follicular lymphoma (FL).
Materials and methods: The incidence and frequency of the major breakpoint cluster region rearrangement in DNA extracted from peripheral blood or lymphoblastoid cell lines from 481 normal individuals was determined using a TaqMan real-time polymerase chain reaction assay (PE Applied Biosystems, Foster City, CA).
Results: Twenty three percent of samples were positive for the Bcl-2/IgH rearrangement, with approximately 3% of these at levels of more than 1 in 10(4) cells.
Conclusion: The presence of circulating Bcl-2/IgH+ cells, other than those derived from the malignant clone, could confound the detection and quantitation of minimal residual disease in patients with FL, particularly at low levels of tumor burden.