Evaluating New Markers for Minimal Residual Disease Analysis by Flow Cytometry in Precursor B Lymphoblastic Leukemia

Abstract

Minimal residual disease is currently the most powerful prognostic indicator in Precursor B lymphoblastic leukemia. Multiparameter flow cytometry is the most commonly used modality. Seventy three B ALL cases and 15 normal marrows were evaluated for expression patterns of leukemia markers (CD38, CD58, CD73) in all 73 cases and CD66c, CD86 and CD123 in 23 cases. CD73 was aberrantly expressed in 90.41% cases and CD86 in 60.87% B ALL cases. Thus addition of these markers in MRD panels can increase the sensitivity of the assay.

Keywords: Acute leukemia; Hematology; MRD.

Fig. 1

Figure depicts the templates prepared for Tube 1 (using normal bone marrow samples). The drawn outlines indicate the regions defined as normal (expression patterns of hematogones). In this case there was aberrant expression of CD38, CD58 and CD73 by leukemic blasts (LAIPs for this case)

Fig. 2

Figure depicts the templates prepared for Tube 2 (using normal bone marrow samples). The drawn outlines indicate the regions defined as normal (expression patterns of hematogones). In this case there was aberrant expression of CD66c, CD123 and CD86 by leukemic blasts (LAIPs for this case)

Fig. 3

Figure depicts expression patterns of CD73 and CD86 in a 1 year old child at diagnosis (a) and MRD sample at the end of induction (b). CD73 and CD86 are overexpressed at diagnosis and both served as useful markers for MRD analysis post induction

Fig. 4

a Depicts CD73 overexpression in a 39 year old male patient with B ALL at the time of diagnosis (left column) and MRD analysis at the end of induction (right column). b depicts CD73 overexpression in a 16 year old male patient with B ALL (left column) and MRD analysis at the end of induction (right column)