Cytogenetic risk grouping by the monosomal karyotype classification is superior in predicting the outcome of acute myeloid leukemia undergoing allogeneic stem cell transplantation in complete remission

Impact of pretransplant measurable residual disease on the outcome of allogeneic hematopoietic cell transplantation in adult monosomal karyotype AML

Allogeneic hematopoietic cell transplantation (HCT) is often unsuccessful for monosomal karyotype (MK) acute myeloid leukemia (AML). To what degree failures are associated with pre-transplant measurable residual disease (MRD) – a dominant adverse risk factor – is unknown. We therefore studied 606 adults with intermediate- or adverse-risk AML in morphologic remission who underwent allogeneic HCT between 4/2006 and 1/2019. Sixty-eight (11%) patients had MK AML, the majority of whom with complex cytogenetics. Before HCT, MK AML patients more often tested MRD^pos by multiparameter flow cytometry (49% vs. 18%; P<0.001) and more likely had persistent cytogenetic abnormalities (44% vs. 13%; P<0.001) than non-MK AML patients. Three-year relapse/overall survival estimates were 46%/43% and 72%/15% for MRD^neg and MRD^pos MK AML patients, respectively, contrasted to 20%/64% and 64%/38% for MRD^neg and MRD^pos non-MK AML patients, respectively. After multivariable adjustment, MRD^pos remission status but not MK remained statistically significantly associated with shorter survival and higher relapse risk. Similar results were obtained in several patient subsets. In summary, while our study confirms higher relapse rates and shorter survival for MK-AML compared to non-MK AML patients, these outcomes are largely accounted for by the presence of other adverse prognostic factors, in particular higher likelihood of pre-HCT MRD.

Hematopoietic Cell Transplantation Outcomes in Monosomal Karyotype Myeloid Malignancies

The presence of monosomal karyotype (MK+) in acute myeloid leukemia (AML) is associated with dismal outcomes. We evaluated the impact of MK+ in AML (MK+AML, n = 240) and in myelodysplastic syndrome (MDS) (MK+MDS, n = 221) on hematopoietic cell transplantation outcomes compared with other cytogenetically defined groups (AML, n = 3360; MDS, n = 1373) as reported to the Center for International Blood and Marrow Transplant Research from 1998 to 2011. MK+ AML was associated with higher disease relapse (hazard ratio, 1.98; P < .01), similar transplantation-related mortality (TRM) (hazard ratio, 1.01; P = .90), and worse survival (hazard ratio, 1.67; P < .01) compared with those outcomes for other cytogenetically defined AML. Among patients with MDS, MK+ MDS was associated with higher disease relapse (hazard ratio, 2.39; P < .01), higher TRM (hazard ratio, 1.80; P < .01), and worse survival (HR, 2.02; P < .01). Subset analyses comparing chromosome 7 abnormalities (del7/7q) with or without MK+ demonstrated higher mortality for MK+ disease in for both AML (hazard ratio, 1.72; P < .01) and MDS (hazard ratio, 1.79; P < .01). The strong negative impact of MK+ in myeloid malignancies was observed in all age groups and using either myeloablative or reduced-intensity conditioning regimens. Alternative approaches to mitigate disease relapse in this population are needed.

Prognostic Significance of Monosomal Karyotype in Adult Patients With Acute Myeloid Leukemia Treated With Risk-Adapted Protocols

BACKGROUND

The monosomal karyotype (MK) is a well-known adverse prognostic factor and has been found to be related to poor outcome in patients with acute myeloid leukemia (AML). However, the outcome in MK-positive AML patients undergoing different therapies has not been well investigated.

PATIENTS AND METHODS

We retrospectively analyzed clinical and laboratory features in 225 MK-positive AML patients. Clinical outcome of overall survival (OS) and disease-free survival (DFS) was evaluated in patients according to age group and in patients who received different therapy protocols.

RESULTS

The proportion of MK-positive patients increased along with age. Also, patients who were treated with high-dose cytarabine (HD-Ara-C) as consolidation therapy followed by allogeneic hematopoietic stem cell transplantation (allo-HSCT) demonstrated longer OS and DFS compared to allo-HSCT or HD-Ara-C alone. Patients treated with allo-HSCT alone exhibited longer DFS compared to patients treated with HD-Ara-C alone. No difference in OS was discovered between these 2 single protocols.

CONCLUSION

MK was associated with a lower complete remission rate. HD-Ara-C therapy followed by allo-HSCT could improve the prognosis of MK-positive AML patients.