Emergence of a prominent myeloid clone in a ZNF384-rearranged B-cell
precursor acute lymphoblastic leukaemia post-corticosteroid pre-phase
therapy.
Abstract
A 2-year-old girl with TCF3-ZNF384 re-arranged standard-risk B-cell
precursor acute lymphoblastic leukaemia (BCP-ALL) showed an apparent
lineage-switch to predominantly myeloid blasts following 7-days of
corticosteroid therapy. ZNF384-re-arranged leukemias are increasingly
recognized to present either as mixed-phenotype acute leukemia or as
BCP-ALL with pro-B immunophenotype. Lineage switch is a rare phenomenon
described at relapse or following CAR-T-cell therapy previously mostly
in KMT2A re-arranged leukemias; and now, also in ZNF384-rearranged
patients. It is previously unreported in any patient after pre-phase
corticosteroid therapy. Hematologists should be aware of this distinct
emerging entity among leukemias with multi-lineage differentiation
potential.