General AML

A comparison of autologous and allogenic transplantation in AML patients in first molecular remission

On 11th September 2017, in an article published in the American Journal of Hematology, Norbert-Claude Gorin from the Hôpital Saint-Antoine APHP and colleagues, reported results from their retrospective study, which compared the outcomes of Acute Myeloid Leukemia (AML) patients who underwent either Allogenic Hematopoietic Stem Cell Transplantation (HSCT) with a 10/10 Unrelated Donor (UD) or Autologous Stem Cell Transplantation (ASCT) in first molecular remission.

Using data provided by the Acute Leukemia Working Party (ALWP) of the European Bone Marrow Transplant (EMBT) registry, the authors identified 373 and 335 non high-risk AML patients who were transplanted in first molecular remission using either ASCT or HSCT, respectively, between January 2005 and December 2015. Patients were risk-stratified using the 2010 European Leukemia Net (ELN) classification into either favorable, intermediate group 1, or intermediate group 2. The primary endpoints of the study were two-year post-transplant Leukemia Free Survival (LFS) and Overall Survival (OS).

The key results of the study were:
  • ELN favorable group
    • Survival in patients who underwent ASCT (n = 234) and UD (n = 70)
      • LFS; 67% vs 64%
      • OS; 83% vs 62%, P = 0.008
    • ASCT was significantly associated with better OS (HR = 2.08, P = 0.04) and lower Non Relapse Mortality (NRM [HR = 3.98, P = 0.013]) compared to UD
  • ELN intermediate group 1
    • Survival in patients who underwent ASCT (n = 87) and UD (n = 172)
      • LFS; 39% vs 70%, P < 10-6
      • OS; 61% vs 74%, P = 0.005
    • UD transplants were significantly associated with lower Relapse Incidence (RI [HR = 0.24, P < 10-5]), better OS (HR = 0.53, P = 0.01), and LFS (HR = 0.36, P < 10-5)
  • ELN intermediate group 2
    • Survival in patients who underwent ASCT (n = 52) and UD (n = 93)
      • LFS; 60% vs 64%, P = 0.8
      • OS; 74.5% vs 70.6%, P = 0.94
    • UD transplants were significantly associated with higher NRM (HR = 6.12, P = 0.03)

In summary, patients in the ELN favorable risk group benefit better from ASCT compared to HSCT. Moreover, patients in the intermediate risk group 1 benefit more from HSCT, while patients in the intermediate risk group 2 had similar outcomes with ASCT and HSCT.

The authors discussed that their study had several limitations including its retrospective nature. They suggest, however, that their findings ‘may justify’ the inclusion of ASCT in randomized studies of AML patients in molecular remission.

The results of this study were presented orally at the 43rd Annual meeting of the EBMT, Marseille, France, March 26–29 2017.

Abstract

Patients with Acute Myelogenous Leukemia have a better outcome if reaching molecular remission.

We compared the outcome of 373 patients autografted and 335 patients allografted with a 10/10 compatible unrelated donor in first molecular remission.

Patients were stratified using the ELN European Leukemia Net classification.

ELN favorable group: (234 auto and 70 unrelated transplants). By univariate analysis, in the auto group, the Non Relapse Mortality (NRM) was lower (3.7% versus 19%; p< 10−4), Relapse Incidence (RI) higher (29% versus 17%, p< 10−4), Leukemia Free Survival (LFS) identical (67% versus 64%) and Overall Survival (OS) better than in the allogeneic group (83% versus 62%; p=0.008). By multivariate analysis, autologous transplantation was associated with a lower NRM (HR: 4, p =0.01) and a better OS (HR: 2.08, p= 0.04).

ELN intermediate group 1: (87 autologous and 172 unrelated transplants). By univariate analysis, in the auto group, NRM was lower (2.5% versus 11.8%; p= 0.03), RI higher (59% versus 18%, p< 10−6), LFS lower (39% versus 70%; p< 10−6) and OS lower than in the unrelated donor group (61% versus 74%; p=0.005). By multivariate analysis, unrelated donor was superior to autologous transplantation for LFS (HR: 0.36, p < 10−5) and OS (HR: 0.53, p= 0.01).

ELN intermediate group 2: (52 autologous and 93 unrelated donors). The outcome was identical.

We conclude that good risk patients get higher benefit from autologous transplantation. Intermediate risk 2 patients have the same outcome and Intermediate risk 1 patients get higher benefit from unrelated donor transplants.

References
  1. Gorin N.C. et al. Unrelated matched versus autologous transplantation in adult patients with good and intermediate risk acute myelogenous leukemia in first molecular remission. Am J Hematology. 2017 Sep 11. DOI: 10.1002/ajh.24904. [Epub ahead of print].