BCR-ABL1 positive AML or CML in blast crisis? A pediatric case report with inv(3) and t(9;22) in the initial clone

Cancer Genet. 2021 Jun:254-255:70-74. doi: 10.1016/j.cancergen.2021.02.007. Epub 2021 Feb 19.

Abstract

The co-occurrence of an inversion inv(3)(q21q26)/GATA2-MECOM and a Philadelphia translocation t(9;22)(q34;q11)/BCR-ABL1 in the context of chronic myeloid leukemia (CML) in blast crisis or acute myeloid leukemia (AML) has only rarely been described. To our knowledge, this co-occurrence has been reported in six pediatric patients with CML but not in pediatric patients with AML. Here, we report on a 7-year-old girl, who, presented with a t(9;22) and inv(3) in 14 of 15 metaphases and an additional monosomy 7 was detected in 5 of these metaphases (ISCN: 46,​XX,​inv(3)(q21q26),​t(9;22)(q34q11)[9]/45,​idem,​-7[5]/46,​XX[1]). The p190 BCR-ABL1 fusion transcript was detected by multiplex PCR and targeted RNA sequencing. Due to these results, a clear distinction between a CML in blast crisis and a BCR-ABL1 positive AML was not possible. The patient was treated according to the treatment recommendations of the AML-BFM study group and additionally received tyrosine kinase inhibitor therapy (Dasatinib). The treatment with Dasatinib was successful in eliminating the inv(3)/t(9;22) clone, but the ancestral inv(3) clone persisted. Based upon these findings we diagnosed an AML with inv(3) and a secondary acquisition of t(9;22). This treatment as well as an allogenic transplantation has led to a complete remission of the disease up to this date (21 months post diagnosis).

Keywords: Acute myeloid leukemia (AML); BCR-ABL1; Chronic myeloid leukemia (CML); GATA2-MECOM; Next generation sequencing (NGS).

Publication types

  • Case Reports
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Blast Crisis / genetics*
  • Child
  • Chromosome Inversion / genetics*
  • Chromosomes, Human, Pair 22 / genetics*
  • Chromosomes, Human, Pair 9 / genetics*
  • Clone Cells / pathology
  • Cytogenetic Analysis
  • Fusion Proteins, bcr-abl / genetics*
  • Fusion Proteins, bcr-abl / metabolism
  • Humans
  • Leukemia, Myelogenous, Chronic, BCR-ABL Positive / genetics*
  • Leukemia, Myeloid, Acute / genetics*
  • Translocation, Genetic*

Substances

  • BCR-ABL1 fusion protein, human
  • Fusion Proteins, bcr-abl