BCR-ABL fusion protein detection in peripheral blood and bone marrow samples of adult precursor B-cell acute lymphoblastic leukemia patients using the flow cytometric immunobead assay

Background: The ability to detect the BCR-ABL fusion gene in precursor B-cell acute lymphoblastic leukemia (pB-ALL) is essential for making accurate treatment decisions. Methods: We used a new flow cytometric immunobead assay for BCR-ABL fusion protein detection in peripheral blood and/or bone marrow samples from 38 adult pB-ALL patients and the results were compared with polymerase chain reaction (PCR) detection of BCR-ABL transcript. Results: The fusion protein was detected in peripheral blood and bone marrow samples from seven of the 38 (18%) patients, and results for both the p190 and p210 were confirmed by PCR. One case, which was positive by cytogenetics and fluorescence in situ hybridization (FISH), was negative by PCR but positive by flow cytometry. Another case, which was positive by PCR and negative by flow cytometry, was from a patient on steroid treatment. Conclusions: The cytometric immunobead assay for BCR-ABL fusion protein detection was found to be suitable for the investigation of pB-ALL patients. This assay is reliable, rapid and simple to use for peripheral blood and bone marrow samples.