Survival of Patients with Acute Myeloid Leukemia after Allogeneic Stem Cell Transplantation: An Experience in Developing Country

Abstract

Background: Allogeneic stem cell transplantation (allo-SCT) is the highest potential treatment for long-term survival as post-remission therapy for acute myeloid leukemia (AML). The aim of this study was to estimate the overall survival (OS) of patients with AML after allo-SCT and to identify the factors affecting them as a prognostic factor for the survival of patients. Material and Methods: In this retrospective cohort study, data of patients with AML who underwent allo-SCT at Taleghani bone marrow transplantation and cell therapy center in Tehran, Iran, from May 2009 to September 2016 were used. A total of 101 patients were enrolled and death time was considered as a failure event for them. Kaplan-Meier method, log-Rank tests, and Cox proportional hazard model were used to evaluate OS and to identify the risk factors of patient's survival. The SPSS software version 21 was used for the analysis of data and P<0.05 was considered as a significant level. Results: Of 101 patients with AML, 49 (48.5%) were males. The median age at allo-SCT was 32.76 years and 42 patients (41.6%) died. The 5-year OS and disease-free survival (DFS) was 56% (95%CI: 51-61%) and 52% (95%CI: 57-47%), respectively. Multivariate analysis by Cox regression indicated that OS has a significant relationship with primary WBC count and relapse (P=0.001). Conclusion: Our results showed that allo-SCT has nearly the same outcome in developing countries and the WBC count and relapse are effective factors on the chance of survival in AML patients after allo-SCT.

Keywords: Acute myeloid leukemia; Allogeneic stem cell transplantation; Prognostic factors; Survival analysis.

Figure 1

Kaplan-Meier estimated overall survival of AML patients after allo-SCT according to WBC counts, there was a strong correlation between OS and WBC counts of patients after transplantation (P=0.001), those patients with WBC more than (10×10⁸/ml), their OS was about 4.06 times shorter than the others.

Figure 2

Kaplan-Meier estimated overall survival of AML patients after allo-SCT according to different types of AML (M2, M4 and M5), there was a correlation between OS and the type of AML of patients after transplantation (P=0.02), those patients with AML-M2, their OS was about 10.3 times shorter than the others (AML-M4 and AML-M5).