Impact of Cytomegalovirus Reactivation Following Allogeneic Hematopoietic Cell Transplantation on the Relapse of Acute Leukemia

Abstract

Background

Cytomegalovirus (CMV) reactivation following allogeneic hematopoietic cell transplantation (HCT) is a significant complication; however, its impact on relapse remains controversial.

Objectives

This study aimed to evaluate the clinical impact of CMV reactivation on relapse and survival after HCT in patients with acute leukemia.

Study Design

We conducted a retrospective analysis of 1258 patients diagnosed with acute myeloid leukemia (AML) and acute lymphoblastic leukemia (ALL) who underwent their first HCT between 2000 and 2020.

Results

Our cohort included 871 patients with AML and 387 patients with ALL. Among all patients, 751 (61.6%) experienced CMV reactivation within one year post-HCT. CMV reactivation was associated with HCT from unrelated donors, anti-thymocyte globulin use, and the occurrence of acute graft-versus-host disease. Notably, CMV reactivation was associated with a lower risk of relapse (HR, 0.713; P = .001) and improved event-free survival (HR, 0.743; P = .001) in both AML and ALL patients. However, there was no significant difference in non-relapse mortality or overall survival according to CMV reactivation.

Conclusion

These results suggest that CMV reactivation may prevent post-HCT relapse and enhance event-free survival in AML and ALL patients. Therefore, a CMV prophylaxis strategy is warranted to establish a safe range of CMV reactivation titers that can yield beneficial effects.