**Abstract**

Minimal residual disease (MRD) in acute myeloid leukemia (AML) is a complex, multi-modality assessment and much as its clinical implications at different points are extensively studied, it remains even now a challenging area. It is the disease biology that governs the modality of MRD assessment; in patients harboring specific molecular targets, high sensitivity techniques can be applied. In AML patients undergoing allogenic hematopoietic stem cell transplantation (alloHSCT), relapse in considered as leading cause for treatment failure. In posttransplant setting, regular MRD status assessment enables to identify patients at risk of impending relapse when early therapeutic intervention may be beneficent. We analyzed data of AML patients who underwent matched unrelated donor (MUD) HSCT since the introduction of this procedure in the Republic of North Macedonia. Chimeric fusion transcripts were identified in three patients; two of them positive for RUNX-RUNX1T1 transcript and one for CBFB-MYH11. One patient harbored mutation in the transcription factor CCAAT/enhancer binding protein α (*CEBPA*). Post-transplant MRD kinetics was measured by quantitative polymerase chain or multiplex fluorescent-PCR every three months after the transplantation during the first two years after the transplant. MRD negativity was achieved in three patients by the sixth month of HSCT, who were pre-transplant MRD positive. They sustained hematological and molecular remission for 19, 9 and 7 months, respectively. The forth patient died due to transplant-related complication. Our experience suggests, when molecularly-defined AML patients undergo HSCT, regular MRD monitoring helps predict impending relapse and direct future treatment strategies.

**Keywords:** minimal residual disease (MRD), molecular monitoring, matched unrelated donor (MUD) hematopoietic stem cell transplantation (HSCT), acute myeloid leukemia (AML)
