Detection of minimal residual disease in childhood B-ALL by flow cytometry / 中华血液学杂志

ABSTRACT

<p><b>OBJECTIVE</b>To establish a flow cytometric method for detecting minimal residual disease (MRD) in children with B-ALL and evaluate its clinical application.</p><p><b>METHODS</b>Fifty-eight childhood B-ALL cases entered this study and 30 MRD analyses were performed after remission induction therapy. Four-color fluorochrome labeled monoclonal antibodies were used to analyze the cell immunophenotypes. Cells from normal bone marrow were used as controls. The leukemic cell populations located in flow cytometry dot plots different from those of normal were considered to be the markers of interest in the first step screening, and then used to monitor MRD step after therapy.</p><p><b>RESULTS</b>Fifty-eight cases of childhood B-ALL were screened for antibodies combinations of interest and were identified in 89.7% (52/58) of these cases. The four-color antibody combinations consisted of CD(10)/CD(34)/CD(19) plus another effective marker such as CD(38), CD(65), CD(66c), CD(21). The sensitivity of this method was 0.01%, much higher than microscopic inspection. In 8 cases whose bone marrow microscopically showed no residual leukemic cells, the percentage of leukemic cells were identified with this method of 0.028%, 1.430%, 3.050%, 0.015%, 5.660%, 2.700%, 0.027%, and 0.069%, respectively.</p><p><b>CONCLUSION</b>The application of flow cytometry in MRD monitoring can significantly improve the detection sensitivity in childhood B-ALL, thus facilitate the further treatment decision and follow-up.</p>