Irradiation free conditioning regimen is associated with high relapse rate in Egyptian patients with acute lymphoblastic leukemia following allogeneic hematopoietic stem cell transplantation

Mona Mahrous Abdelaty,Ibrahim Kabbash,Gamal M Fathy,Amr Gawaly,Atef Taha

doi:10.1186/s43046-020-00042-4

Mona Mahrous Abdelaty, Ibrahim Kabbash + Show 3 more

Open Access

https://doi.org/10.1186/s43046-020-00042-4

Copy DOI

Abstract

BackgroundAllogeneic hematopoietic stem cell transplantation (Allo-HSCT) is a curative treatment for adult patients with acute lymphoblastic leukemia (ALL). Cyclophosphamide plus total body irradiation (TBI/Cy) or plus busulfan (Bu/Cy) is a widely used pre-transplant conditioning regimen for ALL. We retrospectively compared the overall survival (OS), disease-free survival (DFS), and other transplant outcomes of allo-HSCT in 119 adult patients with ALL who received an HLA-matched sibling allo-HSCT using TBI-based versus non-TBI-based conditioning regimens. Patients were divided into two groups by their conditioning regimen: TBI/Cy or Bu/Cy.ResultsMedian OS was 11 months in the TBI/Cy group and 6.2 months in the Bu/Cy group. Median DFS was 11.1 months in the TBI group versus 6.8 months in the Bu group, without a statistically significant difference. A higher risk of relapse was observed with the Bu/Cy regimen (HR 2.709, CI 95% 1.106 to 6.638, p = 0.029). Patients who received a transplant in ≥ CR2 were associated with poor DFS.ConclusionDespite the high relapse rate in the non-TBI regimen (Bu/Cy), both regimens had no statistically significant differences in OS, DFS, and NRM. Additional prospective studies are indeed warranted to evaluate the long-term outcomes of radiation-free regimens, including oral and intravenous busulfan, and compare these regimens with TBI-based ones.

Highlights

Allogeneic hematopoietic stem cell transplantation (Allo-HSCT) is a curative treatment for adult patients with acute lymphoblastic leukemia (ALL)
It is still challenging in adults as it is associated with poor survival outcomes and high relapse rates when treated with chemotherapy alone
Allo-HSCT outcome was assessed with the following parameters: time to engraftment, acute and chronic graft versus host disease (GVHD), incidence and severity of infections, and conditioning regimen-related toxicities

Summary

Introduction

Allogeneic hematopoietic stem cell transplantation (Allo-HSCT) is a curative treatment for adult patients with acute lymphoblastic leukemia (ALL). Patients were divided into two groups by their conditioning regimen: TBI/Cy or Bu/Cy. ALL generally has an excellent prognosis in children with promising chemotherapy regimens [1]. ALL generally has an excellent prognosis in children with promising chemotherapy regimens [1] It is still challenging in adults as it is associated with poor survival outcomes and high relapse rates when treated with chemotherapy alone. Allo-HSCT is generally considered a Combinations of cyclophosphamide with either TBI or busulfan are the most commonly used myeloablative conditioning regimens (MAC) for allo-HSCT in adult ALL [3]. TBI has dual immunosuppressive and antileukemic properties with the ability to reach the hidden sites. It has expected better survival outcomes without an increase in relapse or transplant-related mortality (TRM). At higher doses, TBI is associated with a potential risk of early and late complications [4]

Methods

Results

Discussion

Conclusion