Marker chromosome is a strong poor prognosis factor after allogeneic HSCT for adverse‐risk AML patients

Introduction Chromosome analysis is necessary for the risk classification of acute myeloid leukemia (AML). Marker chromosome (MC) is a fragmented chromosome whose origin cannot be identified from other chromosomes and originates from marked genomic instability. Although AML with MC (MC+) has a poor prognosis even after intensive chemotherapy, its influence on the outcome after allogeneic hematopoietic stem cell transplantation (allo‐HSCT) is unclear. Objective and Methods We retrospectively analyzed 162 AML patients after allo‐HSCT. To evaluate the significance of MC, we compared it with other chromosomal abnormalities. Result Marker chromosome was detected in 14 (8.6%, MC+) patients (vs MC−, n = 158). The 2‐year overall survival (OS) in MC+ vs MC− was 26.8% vs 62.2% (P = .0098). The 2‐year cumulative incidence of relapse (CIR) in MC+ vs MC− was 80.4% vs 35.5% (P = .0004). Among adverse‐risk AML (AD‐AML, n = 36), AD‐AML/MC+ (n = 11) demonstrated a poorer 2‐year OS (9.1%, vs AD‐AML/MC− n = 25, 58.3%, P = .0031) and higher 2‐year CIR (89.6%, vs AD‐AML/MC− 44.7%, P = .002). In multivariate analysis, MC (HR 3.08, 95% CI; 1.02‐9.29, P = .046) and HCT‐CI (HR 3.23, 95% CI; 1.00‐10.4, P = .049) were independent risk factors for CIR among AD‐AML. Conclusion Our study suggests MC as a new independent factor for chromosome risk classification to further classify AD‐AML.