The mixed-lineage leukemia (MLL) gene is located on chromosome 11q23. The MLL gene can be rear‑ ranged to generate partial tandem duplications (MLL-PTD), which occurs in about 5-10% of acute myeloid leukemia (AML) with a normal karyotype and in 5-6% of myelodysplastic syndrome (MDS) patients. Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is currently one of the curative therapies available for AML and MDS with excess blasts (MDS-EB). | Kong et al. BMC Cancer 2022 22 11 https s12885-021-09051-5 RESEARCH Open Access Monitoring of post-transplant MLL-PTD as minimal residual disease can predict relapse after allogeneic HSCT in patients with acute myeloid leukemia and myelodysplastic syndrome Jun Kong1 Meng Ge Gao1 Ya Zhen Qin1 Yu Wang1 Chen Hua Yan1 2 Yu Qian Sun1 Ying Jun Chang1 2 3 Lan Ping Xu1 2 Xiao Hui Zhang1 Kai Yan Liu1 Xiao Jun Huang1 2 3 4 and Xiao Su Zhao1 2 3 Abstract Background The mixed-lineage leukemia MLL gene is located on chromosome 11q23. The MLL gene can be rear ranged to generate partial tandem duplications MLL-PTD which occurs in about 5-10 of acute myeloid leukemia AML with a normal karyotype and in 5-6 of myelodysplastic syndrome MDS patients. Allogeneic hematopoietic stem cell transplantation allo-HSCT is currently one of the curative therapies available for AML and MDS with excess blasts MDS-EB . However how the prognosis of patients with high levels of MLL-PTD after allo-HSCT and whether MLL-PTD could be used as a reliable indicator for minimal residual disease MRD monitoring in transplant patients remains unknown. Our study purposed to analyze the dynamic changes of MLL-PTD peri-transplantation and the best threshold for predicting relapse after transplantation. Methods We retrospectively collected the clinical data of 48 patients with MLL-PTD AML or MDS-EB who underwent allo-HSCT in Peking University People s Hospital. The MLL-PTD was examined by real-time quantitative polymerase chain reaction RQ-PCR at the diagnosis before transplantation and the fixed time points after transplantation. Detectable MLL-PTD ABL gt was defined as MLL-PTD positive in this study. Results The 48 patients included 33 AML patients and 15 MDS-EB patients. The median follow-up time was 26 56 months after HSCT. In AML patients 7 patients died of treatment-related mortality TRM 6 patients underwent hematological relapse and died ultimately. Of the 15 patients .
