[Detection of minimal residual disease in childhood B-ALL by flow cytometry].
OBJECTIVE
To establish a flow cytometric method for detecting minimal residual disease (MRD) in children with B-ALL and evaluate its clinical application.


METHODS
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.


RESULTS
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.


CONCLUSIONS
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.
Xu
Chong
C
Laboratory Diagnostic Center, Xin Hua Hospital, Shanghai Children's Medical Center, Shanghai Second Medical University, Shanghai 200127, China.
Zhao
Hui-jun
HJ
Wu
Zheng-hong
ZH
Xue
Hui-liang
HL
Tang
Jing-yan
JY
Chen
Jing
J
Pan
Ci
C
Chen
Jing
J
Li
Li
L
Gu
Long-jun
LJ
Shen
Li-song
LS
D002051:Burkitt Lymphoma / Q000175:diagnosis*; D002648:Child; D005434:Flow Cytometry / Q000379:methods*; D006801:Humans; D018365:Neoplasm, Residual; D012680:Sensitivity and Specificity