Standardizing minimal residual disease by flow cytometry for precursor B lineage acute lymphoblastic leukemia in a developing country

Authors


  • How to cite this article: Patkar N, Alex AA, Bargavi B, Ahmed R, Abraham A, George B, Vishwabandya A, Srivastava A, Mathews V. Standardizing minimal residual disease by flow cytometry for precursor B lineage acute lymphoblastic leukemia in a developing country. Cytometry Part B 2012; 82B: 252–258.

Abstract

Background:

In addition to standard risk criteria at diagnosis, minimal residual disease (MRD) following initiation of therapy is a well-recognized risk factor to predict relapse. Literature from developing countries addressing therapeutic or laboratory practices related to MRD, is largely lacking. In a first paper from India, we describe our experience in establishing a flow cytometry-based MRD assay for precursor B lineage ALL (BCP-ALL) with emphasis on the assay standardization and cost.

Methods:

Normal templates for B cell development were established in 10 control patients using CD45, CD11a, CD38, CD20, CD10, CD19, CD58, CD34, CD123, and CD22. BCP-ALL samples (n = 42) were characterized at diagnosis to identify a suitable marker for follow-up during mid (D+21) and end of induction (D+33). Both, multiparametric immunophenotyping and single marker detection of LAIP were used for data analysis.

Results:

In 95.2% of BCP-ALL at least two informative markers could be obtained when a minimum of four cocktail combinations were used. The combination CD20, CD10, CD45, and CD19 was the most useful (71.4%) followed by combinations containing CD38 (66.7%), CD22 (57.1%), CD11a (52.4%), and CD58 (33.3%). Using our approach, 60 and 47% of patients had detectable MRD at mid and end induction time points, respectively.

Conclusion:

We have described a relatively cost effective MRD panel which is applicable to over 90% of patients. We hope that this data would encourage more centers in India and other resource constrained health delivery systems to develop MRD assays. © 2012 International Clinical Cytometry Society

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