Effect of peritransplant measurable residual disease clearance in patients with myelodysplastic neoplasm: a referral center experience.

Pre-allogeneic stem cell transplant (pre-HSCT) measurable residual disease (MRD) is increasingly recognized as a prognostic marker. However, the MRD status in myelodysplastic neoplasm (MDS) or myelodysplastic/myeloproliferative neoplasm (MDS/MPN) are less well-defined. We performed a retrospective chart review of adults who underwent HSCT for MDS or MDS/MPN in 2012-2023 and evaluated the effect of pre-HSCT MRD status on relapse-free survival (RFS) and overall survival (OS). A conditional analysis of outcomes based on day+90 post-HSCT MRD status was also performed. There were 38 and 55 patients in MRD- and MRD+ cohorts respectively. Baseline patient characteristics, including age, Revised and Molecular International Prognostic Scores (IPSS-R and IPSS-M), and HSCT-related factors were similar between cohorts. The MRD+ cohort had inferior RFS (HR: 1.84, 95% CI: 1.09-3.12, p = 0.02) but a statistically significant difference in OS was not evidenced (HR: 1.52, 95% CI: 0.88-2.61, p = 0.14). After adjusting for % blasts at diagnosis, and conditioning intensity, patients in MRD+ cohort were 1.92 times at increased risk of relapse or death (95% CI: 1.12-3.28, p = 0.02). Additionally, increasing IPSS-M score was associated with poorer RFS (HR: 1.27, 95% CI: 1.01-1.59, p = 0.04) and OS (HR: 1.52, 95% CI: 1.20-1.91, p < 0.01). Among patients who were alive and in remission until day +90 post-HSCT, the pre-HSCT MRD status did not confer a statistically significant difference in RFS and OS if they became MRD- by day +90 post-HSCT. Post-HSCT MRD surveillance should be performed routinely in MDS patients.