Reduced intensity conditioning of allogeneic hematopoietic stem cell transplantation for myelodysplastic syndrome and acute myeloid leukemia in patients older than 50 years of age: a systematic review and meta-analysis

Abstract

Purpose: A systematic review and meta-analysis were performed to explore the efficacy and safety of allogeneic hematopoietic stem cell transplantation with a reduced intensity conditioning regimen in elderly patients with myelodysplastic syndrome (MDS) or acute myeloid leukemia (AML).

Methods: Overall survival (OS) and event-free survival (EFS) were established as the primary endpoints for directly assessing the efficacy, and non-relapse mortality (NRM) for safety. The eligible patients were at or above 50 years of age, and the outcomes of the typical elderly patients (≥60 years) were analyzed individually.

Results: The pooled estimates (95% confidence interval (CI)) for 1-year OS, EFS and NRM were 65 (55-74) %, 50 (44-55) % and 26 (21-30) %, respectively; as for the patients ≥60 years of age, these were 63 (53-72) %, 46 (41-50) % and 28 (23-32) %, respectively. No significantly statistical difference achieved between MDS and AML patients in 1-year EFS and NRM [relative risk (RR) 0.91, 95% CI 0.80-1.04; P = 0.172 and RR 1.18, 95% CI 0.82-1.69; P = 0.365]. The patients with lower diseases risk had the possibility of higher OS rate at ≥ 3 years than those with higher diseases risk (RR 1.37, 95% CI 0.95-1.97; P = 0.088). The patients had significantly higher 2-year OS and EFS rates in complete remission (CR, CR1 and CR2) at transplantation compared to those with advanced diseases (P < 0.05).

Conclusions: RIC-alloHSCT is a feasible treatment option for the patients older than 50 year of age with MDS and AML. Advanced diseases status and higher diseases risk may be the poor factors for prognosis.

Keywords: Acute myeloid leukemia; Elderly; Meta-analysis; Myelodysplastic syndrome; Reduced intensity conditioning; Stem cell transplantation.

Fig. 1

Flowchart describing the process of the systematic search and selection

Fig. 2

Forest plots of pooled estimates (95% CI) for OS and EFS at 1, 2 and ≥3 years (a OS at 1 year; b OS at 2 years; c OS ≥3 years; d EFS at 1 year; e EFS at 2 years; f EFS ≥3 years; a, b, c, d, a1, a2, a3, b1, b2 and b3 mean different data from same studies)

Fig. 3

Forest plots of the relative risks for the patients in CR (a CR1; b CR2) and those with advanced diseases in 2-year OS and EFS

Fig. 4

Forest plots of pooled estimates (95% CI) for GVHD (a grade II–IV aGVHD; b extensive cGVHD; c grade II–IV aGVHD after ATG; d extensive cGVHD after ATG; a, b, c, d, a1, a2, a3, b1, b2 and b3 mean different data from same studies)

Fig. 5

Forest plots of pooled estimates (95% CI) for NRM at 100 days, 1, 2 and ≥ 3 years (a NRM at 100 days; b NRM at 1 year; c NRM at 2 years; d NRM ≥3 years; a, b, c, d, a1, a2, a3, b1, b2 and b3 mean different data from same studies)