Comparison of transplant outcomes between haploidentical transplantation and single cord blood transplantation in non‐remission acute myeloid leukaemia: A nationwide retrospective study

Abstract

SummaryAllogeneic haematopoietic stem cell transplantation (HSCT) is a potentially curative treatment for some patients with acute myeloid leukaemia (AML) who are refractory to chemotherapy. Cord blood transplantation (CBT) is a reasonable option in such cases because of its rapid availability. Recently, a growing number of human leucocyte antigen (HLA)‐haploidentical related donor HSCTs (haplo‐HSCTs) have been performed, although its effectiveness remains undetermined. Using the Japanese nationwide transplantation registry data, we identified 2438 patients aged ≥16 years who received CBT or haplo‐HSCT as their first transplant for non‐remission AML between January 2008 and December 2018. After 2:1 propensity score matching, 918 patients in the CBT group and 459 patients in the haplo‐HSCT group were selected. In this matched cohort, no significant difference in overall survival (OS) was observed between the CBT and haplo‐HSCT groups (hazard ratio [HR] of haplo‐HSCT to CBT 1.02, 95% confidence interval [CI] 0.89–1.16). Similarly, no significant difference in the cumulative incidence of relapse (HR 1.09, 95% CI 0.93–1.28) or non‐relapse mortality (HR 0.94, 95% CI 0.76–1.18). Subgroup analysis showed that CBT was significantly associated with preferable OS in patients receiving myeloablative conditioning. Our data showed comparable outcomes between haplo‐HSCT and CBT recipients with non‐remission AML.

Cord blood versus haploidentical transplantations for non‐remission acute myeloid leukaemia: Authors' reply

“…1 Our study analysed propensity score-matched pairs of patients with acute myeloid leukaemia (AML) in non-remission who underwent CBT or haploidentical haematopoietic stem cell transplantation (haplo-HSCT). 2 The study results showed that outcomes were comparable for CBT and haplo-HSCT overall, but subgroup analysis restricted to patients using MAC showed significantly better overall survival with CBT.…”

Lower probability of relapse after myeloablative cord blood transplantation for patients with refractory AML

“…Lower probability of relapse after myeloablative cord blood transplantation for patients with refractory AML Matsuda et al 1 recently described the outcomes of patients with 'non-remission' acute myeloid leukaemia (AML) after haematopoietic stem cell transplantation (HSCT) using readily available alternative donors: cord blood (CB) and haplo-identical (Haplo) donors. This very well written manuscript, however, did not emphasize an important finding: that patients with active disease who received a myeloablative CB transplant had an approximately 1.5-fold higher probability of survival compared to those with haplo-donors.…”

“…Since these transplants are urgent, rapidly available donor sources are required, and these include CB and haplodonors. The paper of Matsuda et al 1 describes a retrospective comparison of outcomes of recipients of unrelated CB grafts (n = 918) and those of haplo-HSCT (n = 459) from the Japanese Registry. These two groups were selected of a total of 2438 'non-remission' AML patients with ages of 16-65 years transplanted during the period January 2008-December 2018, after 2:1 propensity matching.…”

“…In the Seattle study the relapse probability was twofold lower after CB compared to matched or mismatched bone marrow (BM) grafts. Matsuda et al 1 showed that CB transplants following myeloablative treatment have 'preferable' survival (quoting the authors) in comparison to haplo-HSCT, even in AML patients with refractory disease. The favourable outcomes were driven by the lower relapse rates in this group also.…”

Don't forget cord blood in non‐remission acute myeloid leukaemia!

“…In this issue Matsuda et al report on the largest retrospective registry study comparing the outcomes of not‐in‐remission acute myeloid leukaemia (AML), allografted with single cord blood (sCB) or haploidentical donor 1 …”