A concordant leukemia is that which occurs in a pair of monozygotic twins; a similar genetic background suggests an in utero monoclonal origin. We present the case of a pair of monozygotic infants with concordant acute myeloid leukemia who underwent a peripheral blood hematopoietic stem-cell transplant (HSCT) from a single, younger human leukocyte antigen-identical sibling donor, using a fractioned graft collected during only one apheresis procedure. Twin A relapsed at +456 and received a second haploidentical HSCT from his father, twin B has been in complete remission since the first HSCT. Both children are in complete remission and with negative minimal residual disease at +900 (after second transplant) and +1488, respectively.
Keywords: bone marrow transplantation; concordant leukemia; infant acute leukemia; matched sibling donor; measurable residual disease; myelodysplastic syndrome; peripheral blood stem cell; single apheresis; twins; younger donor.
© 2020 Oscar Gonzalez-Llano.