AUTHOR=Malagola Michele , Polverelli Nicola , Beghin Alessandra , Bolda Federica , Comini Marta , Farina Mirko , Morello Enrico , Radici Vera , Accorsi Buttini Eugenia , Bernardi Simona , Re Federica , Leoni Alessandro , Bonometti Davide , Brugnoni Duilio , Lanfranchi Arnalda , Russo Domenico TITLE=Bone marrow CD34+ molecular chimerism as an early predictor of relapse after allogeneic stem cell transplantation in patients with acute myeloid leukemia JOURNAL=Frontiers in Oncology VOLUME=13 YEAR=2023 URL=https://www.frontiersin.org/journals/oncology/articles/10.3389/fonc.2023.1133418 DOI=10.3389/fonc.2023.1133418 ISSN=2234-943X ABSTRACT=Background

Minimal residual disease (MRD) monitoring is an important tool to optimally address post-transplant management of acute myeloid leukemia (AML) patients.

Methods

We retrospectively analyzed the impact of bone marrow CD34+ molecular chimerism and WT1 on the outcome of a consecutive series of 168 AML patients submitted to allogeneic stem cell transplantation.

Results

The cumulative incidence of relapse (CIR) was significantly lower in patients with donor chimerism on CD34+ cells ≥ 97.5% and WT1 < 213 copies/ABL x 10^4 both at 1st month (p=0.008 and p<0.001) and at 3rd month (p<0.001 for both). By combining chimerism and WT1 at 3rd month, 13 patients with chimerism < 97.5% or WT1 > 213 showed intermediate prognosis. 12 of these patients fell in this category because of molecular chimerism < 97.5% at a time-point in which WT1 was < 213.

Conclusions

Our results confirm that lineage-specific molecular chimerism and WT1 after allo-SCT (1st and 3rd month) are useful MRD markers. When considered together at 3rd month, CD34+ molecular chimerism could represent an earlier predictor of relapse compared to WT1. Further studies are necessary to confirm this preliminary observation.