ISSN: 2329-6917
Sujaya Mazumder, Prabhu Manivannan*, Chandni Bhandary, Rakhee Kar, Smita Kayal, Debdatta Basu
Purpose: The importance of Measurable Residual Disease (MRD) detection in B-acute lymphoblastic leukemias (BALL), has led to identifying ways to increase the sensitivity of detecting MRD by multicolor flow cytometry (MFC) and distinguishing it from the hematogones. The identification of cost-effective panel by MFC is necessary and hence this study was undertaken with an objective to propose a presumptive single tube ten-color antibodies panel for MRD detection by the analysis of immunophenotypic profile of BALL with respect to seven newer Leukemia-Associated Immunophenotype (LAIP) markers at diagnosis namely CD9, CD44, CD58, CD73, CD81, CD86 and CD123, in addition to six backbone markers (CD45, CD34, CD38, CD10, CD19 and CD20) which would be useful in a resource constrained setting.
Methods: This was a retrospective, cross-sectional study. All newly diagnosed cases of BALL which were diagnosed based on morphology, cytochemistry and immunophenotyping by MFC from the period of October 2019 to April 2021 were included (n=82). The expression pattern of the markers at diagnosis were studied in comparison to that of normal pattern of hematogones maturation.
Results: Over-expression of CD73 (83%) and CD86 (77%) were the most effective markers in establishing LAIP at diagnosis. Under-expression of CD81 was the next most frequent LAIP in 71% cases. CD44 and CD58 were similar to each other in terms of LAIP expression and hence any one of them could be used. CD9 though positive in 94% of the cases showed significant overlap with the marker expression of hematogones (overexpression in only 37%) and CD123 was overexpressed in only 36%.
Conclusions: We propose a single ten-color tube comprising of the markers CD45, CD19, CD34, CD10, CD20, CD38, CD73, CD86, CD81 and CD44 for diagnosis as well as for MRD analysis in the post-therapy samples of BALL in low- and middle-income countries.