No significant prognostic value of normal precursor B‐cell regeneration in paediatric acute myeloid leukaemia after induction treatment

Abstract

SummaryB-cell precursors (BCP) regeneration in bone marrow (BM) after induction chemotherapy is prognostic for good treatment response in adult acute myeloid leukaemia (AML). We detected BCP regeneration in 81% of 59 paediatric AML patients at first complete remission; this compared to 46% in an adult study. BCP regeneration did not correlate with outcome or minimal residual disease levels. In 36 healthy BM controls, BCP levels were significantly higher in children as compared to adults. Therefore, BCP regeneration does not reflect good response to treatment in paediatric AML, possibly due to the relatively high base-line levels of BCP in children.

Early recovery of circulating immature B cells in B‐lymphoblastic leukemia patients after CD19 targeted CAR T cell therapy: A pitfall for minimal residual disease detection

“…Although recovery of B-cell precursors is age dependent, the observations from this series were unlikely attributable to age alone, as our patient were all under the age of 25, and the study by van Wering et al included patients aged 16 and below. This is consistent with literature showing that the presence of neoplastic cells, including (but not limited to) ALL, may suppress recovery of marrow B-cell precursors (20,29). Of interest, we noted a decrease in peripheral blood B-cells in Patient 5 at Day 19 after second CAR-T infusion (Fig.…”

“…B-cell differentiation may be subdivided into 8 stages based on expression of CD19, CD22, CD34, CD10, CD20, CD38, TdT, sIg and cytoplasmic Ig, with stages 1-2 corresponding to Pro-B cells, stages 3-6 corresponding to Pre-B cells, stage 7 corresponding to Immature B-cells, and Mature B-cells in stage 8 (17). The B-cell precursors in healthy children are comprised predominantly of Pre-B-II, Stage 5-6 cells (17), and the number of B-cell precursors in children is significantly higher (median 7.26%) than in healthy adults (median 0.98%) (20), and also holds true in both children (24.6%) and adults (6.3%) with various disease states (29). The patterns of B-cell regeneration in the bone marrow of ALL patients can also reflect the type and timing of chemotherapy that was received.…”

Loss of B cells and their precursors is the most constant feature of GATA-2 deficiency in childhood myelodysplastic syndrome

“…Figure S2), as previously published. 23,24 As expected, AA presented with a lower total progenitor frequency (assessed as CD34 pos or CD117 …”

“…23,24 The lowest proportion of B cells was present in GATA-2-deficient patients (Table 3 and Figure 1). The highest proportion of B cells was present in the AA group, which may be explained by a severe reduction in the myeloid compartment and relative lymphocytosis.…”

Bone marrow immunophenotyping by flow cytometry in refractory cytopenia of childhood

“…In comparison with healthy pediatric controls, the reduction in myeloid blast cells and CD34 + Bcell precursors in RCC patients would probably be even more severe because the precursor compartment in children is relatively larger than in adults. 22,36 In comparison with studies in adult low-grade MDS, we detected relatively few flow cytometric abnormalities in RCC, apart from the severe reduction of myeloid cells. Furthermore, there was a difference in the type of immunophenotypic abnormalities between RCC and adult low-grade MDS.…”