Allogeneic Stem Cell Transplantation in Adult Patients with Acute Myelogenous Leukemia: To Transplant or Not to Transplant? A Systematic Review of International Guidelines.
Authors: Hübel Kai , Weingart Olaf , Naumann Frauke , Bohlius Julia , Wheatley Keith , Engert Andreas 
Published: October 2019

Abstract
Abstract 1419
Poster Board I-442
For more than 20 years high dose chemotherapy followed by allogeneic stem cell transplantation (SCT) has been considered as a reasonable approach for the treatment of patients with AML. Moreover, during the last decade new scientific and technical developments results in major changes of clinical practice of transplantation. Enhanced donor availabilities and new strategies, e.g. dose-reduced conditioning, now make allogeneic stem cell transplantation available to patients who do not have a related donor or would not tolerate high-dose chemotherapy due to age or comorbidities. Usually, the decision to start the work-up process for allogeneic transplantation in AML patients is based on the availability of a donor, the assignment to the cytogenetic risk group, and the response to induction therapy, as well as patient factors. However, there would be greater confidence in defining who should, or should not, receive an allograft if the available recommendations given in guidelines are consistent and similar. In this analysis, a comprehensive systematic literature search for best available evidence from controlled clinical trials was performed in the bibliographic databases MEDLINE, EMBASE and Cochrane Central. In addition, the websites of major organizations in Europe and the US (European Group for Blood and Marrow Transplantation, EBMT; European Society for Medical Oncology, ESMO; British Committee for Standards in Hematology, BCSH; American Society for Blood and Marrow Transplantation, ASBMT; National Comprehensive Cancer Network, NCCN) were screened and the specific databases of the National Guideline Clearinghouse and the Guideline International Network Database were also searched to identify the latest recommendations and guidelines. The following points were selected for systematic comparison of the best available evidence: Factors for risk assessment and categorization of AML, donor categories for allogeneic SCT (sibling donors / matched unrelated donors), allogeneic transplantation in first CR, allogeneic transplantation in relapse/progressive disease or second CR, and allogeneic transplants with reduced intensity conditioning regimen. Several interesting findings emerge from this analysis: 1) For patients with relapse or refractory disease donor availability should be explored and discussed, though this is not based on reliable evidence from randomized studies; 2) Patients in CR1 with intermediate or high risk disease who have a matched related donor available should receive allogeneic stem cell transplantation (intermediate risk; ASBMT: reasonable, NCCN: option); 3) For patients who lack a family donor the recommendations are not consistent; 4) Allogeneic transplantation with reduced conditioning in AML patients is feasible, but the superiority over standard therapeutic regimens has not been proven yet. In summary, current guidelines differ in critical points in the recommendation for allogeneic stem cell transplantation. Furthermore, it is likely that only well-defined subgroups of AML patients will benefit from stem cell transplantation.

Disclosures:
No relevant conflicts of interest to declare.