Iron Overload Is Associated with Delayed Engraftment and Increased Nonrelapse Mortality in Recipients of Umbilical Cord Blood Hematopoietic Cell Transplantation

Association between the pre-transplantation serum ferritin level and outcomes of hematopoietic stem cell transplantation: A systematic review and meta-analysis

Background

Iron overload, as indicated by evaluated serum ferritin (SF) level, occurs commonly in patients with hematological diseases. To evaluate the association between pre-transplant SF level and outcomes of hematopoietic stem cell transplantation (HSCT), we performed this systematic review and meta-analysis.

Methods

PubMed, Embase, Web of Science and the Cochrane Library electronic database were searched from inception to August 2023, and 56 studies with 14149 patients were found to be eligible.

Results

An elevated pre-transplantation SF level was associated with inferior overall survival (hazard ratio [HR],1.77; 95 % confidence interval [CI],1.61-1.96) and disease-free survival (HR, 1.86; 95 % CI, 1.58-2.19), and increased risk of non-relapse mortality (HR, 1.73; 95 % CI, 1.49-2.02), and relapse (HR, 1.46; 95 % CI, 1.29-1.65). However, no meaningful association was observed between SF levels and acute graft-versus-host disease (GVHD) (risk ratio [RR], 1.09; 95 % CI, 0.96-1.24), or chronic GVHD (RR, 0.95; 95 % CI, 0.79-1.16). Furthermore, an elevated pre-transplantation SF level was associated with a higher risk of fungal infection (RR, 1.56; 95 % CI, 1.16-2.10), but not with bacterial infection (RR, 1.09; 95 % CI, 0.80-1.50). Moreover, an elevated pre-transplantation SF level was related to a higher risk of death due to relapse/disease progression (RR, 1.72; 95 % CI, 1.33-2.23) and infection (RR, 2.21; 95 % CI, 1.55-3.15), but not death due to GVHD (RR, 1.18; 95 % CI, 0.79-1.77).

Conclusions

A higher pre-transplantation SF level was significantly associated with a higher risk of relapse/disease progression and infections, which contributed to worse survival in patients undergoing HSCT. In particular, a higher SF level was related to a higher risk of fungal infection, indicating that patients with a higher pre-transplantation SF level require more attention regarding the risk of fungal infection after HSCT.

Impact of platelet transfusion refractoriness in the first 30 days post-hematopoietic stem cell transplantation on outcomes of patients with myelodysplastic syndrome

Introduction

Currently, no study has determined whether platelet transfusion refractoriness (PTR) post-hematopoietic stem cell transplantation (HSCT) before engraftment in patients with myelodysplastic syndrome (MDS) would impacts clinical outcomes.

Methods

We performed a MDS-specific retrospective analysis to determine whether PTR in one-month post-HSCT in patients with MDS could influence outcomes.

Results and discussion

Among the 315 patients enrolled, 110 (34.9 %) had PTR from stem cell infusion to one-month post-HSCT. Baseline characteristics of the PTR and non-PTR groups were similar. We found that patients with PTR had a slower and lower rate of platelet engraftment by day 28, as well as a slower recovery of neutrophils. The median days of neutrophil and platelet engraftment were 14 days (9-23) and 17 days (8-28) in the PTR groups versus 13 days (9-23) and 15 days (7-28) in the non-PTR group (P<0.001). By day 28, 84 of 110 patients (76.4%) with PTR achieved platelet engraftment compared with 181 of 205 patients (88.3%) without PTR achieving platelet engraftment (P=0.007). In addition, patients in the PTR group received significantly more red blood cell (median, 17 units vs. 10 units, P<0.001) and platelet transfusions (median, 13 units vs. 7 units, P<0.001). However, the overall survival was similar between the two groups. PTR in one-month post-HSCT, haploidentical donor, and ferritin level>1041ng/ml (median level) were independent adverse factors of platelet engraftment.

Development of a nomogram to predict the risk of secondary failure of platelet recovery in patients with β-thalassemia major after hematopoietic stem cell transplantation: a retrospective study

Background

Secondary failure of platelet recovery (SFPR) is a common complication that influences survival and quality of life of patients with β-thalassemia major (β-TM) after hematopoietic stem cell transplantation (HSCT).

Objectives

A model to predict the risk of SFPR in β-TM patients after HSCT was developed.

Design

A retrospective study was used to develop the prediction model.

Methods

The clinical data for 218 β-TM patients who received HSCT comprised the training set, and those for another 89 patients represented the validation set. The least absolute shrinkage and selection operator regression algorithm was used to identify the critical clinical factors with nonzero coefficients for constructing the nomogram. Calibration curve, C-index, and receiver operating characteristic curve assessments and decision curve analysis (DCA) were used to evaluate the calibration, discrimination, accuracy, and clinical usefulness of the nomogram. Internal and external validation were used to test and verify the predictive model.

Results

The nomogram based on pretransplant serum ferritin, hepatomegaly, mycophenolate mofetil use, and posttransplant serum albumin could be conveniently used to predict the SFPR risk of thalassemia patients after HSCT. The calibration curve of the nomogram revealed good concordance between the training and validation sets. The nomogram showed good discrimination with a C-index of 0.780 (95% CI: 70.3-85.7) and 0.868 (95% CI: 78.5-95.1) and AUCs of 0.780 and 0.868 in the training and validation sets, respectively. A high C-index value of 0.766 was reached in the interval validation assessment. DCA confirmed that the nomogram was clinically useful when intervention was decided at the possibility threshold ranging from 3% to 83%.

Conclusion

We constructed a nomogram model to predict the risk of SFPR in patients with β-TM after HSCT. The nomogram has a good predictive ability and may be used by clinicians to identify SFPR patients early and recommend effective preventive measures.

Impact of Iron overload and Iron Chelation with deferasirox on outcomes of patients with severe aplastic anemia after allogeneic hematopoietic stem cell transplantation

BACKGROUND

Patients suffering from severe aplastic anemia (SAA) need frequent blood transfusions during allogeneic hematopoietic stem cell transplantation (allo-HSCT). However, these transfusions can result in an excess of iron in the body tissues, which can negatively impact the success of the transplant.

OBJECTIVES

This study aimed to examine the impact of pre-transplant iron overload (IO) on the outcomes of allogeneic hematopoietic stem cell transplantation (allo-HSCT) in patients with severe aplastic anemia (SAA). It also investigated whether iron chelation (IC) therapy was necessary to enhance transplantation outcomes in SAA patients by providing guidelines for determining when excess iron should be chelated.

STUDY DESIGN

The study consisted of two parts: Cohort 1, which was retrospective and conducted from April 2012 to December 2018, divided SAA patients receiving their first allo-HSCT into two groups based on their pre-transplant serum ferritin (SF) levels: the iron overload (IO) group (SF >1000 ng/ml, n=17) and the non-IO group (SF ≤ 1000 ng/ml, n=48). Cohort 2 was a prospective clinical trial conducted from January 2019 to July 2020. It involved SAA patients diagnosed with IO who were treated with iron chelation (IC) therapy using deferasirox (DFX) at a dose of 10-30 mg/kg. Patients were separated into two groups based on their pre-transplant SF levels: the IC success (IC^success) group (SF ≤ 1000 ng/ml, n=18) and the IC failure (IC^failure) group (SF >1000 ng/ml, n=28) groups. All participants were evaluated for the correlation between pre-transplant SF levels and transplantation outcomes. A P-value of less than 0.05 was considered statistically significant.

RESULTS

There was no significant difference in the speed of engraftment for the three lineages or in the incidence of 100-day grade II-IV acute graft-versus-host disease (aGVHD), grade III-IV aGVHD, or 3-year chronic GVHD between the two groups in both cohorts. However, in cohort 1, it was noteworthy that 1-year OS (83.3% vs. 41.2%, p < 0.001) and 3-year OS (83.3% vs. 35.3%, p < 0.001) were significantly worse in the IO group. Furthermore, 180-day TRM (14.6% vs. 47.1%, p = 0.005) and 1-year TRM (16.7% vs. 52.9%, p = 0.002) were significantly higher in the IO group. The IO group was significantly associated with inferior 3-year OS in both univariate and multivariate analyses. In cohort 2, it was found that 1-year OS (42.9% vs. 88.9%, p = 0.003) and 3-year OS (42.9% vs. 83.3%, p = 0.007) were significantly better in the IC^success group, while 180-day TRM (11.1% vs. 39.3%, p = 0.040) and 1-year TRM (11.1% vs. 57.1%, p = 0.003) were significantly lower in the IC^success group. These differences were confirmed in both univariate and multivariate analyses.

CONCLUSIONS

The study involving two cohorts showed that pre-HSCT iron overload has a negative impact on transplantation outcomes in SAA patients. Chelating excess iron with a serum ferritin level below 1000 ng/ml was found to be necessary and could potentially improve the outcomes.

Impact of iron overload in hematopoietic stem cell transplantation

Iron overload (IOL) is a common condition in patients with hematological malignancies(HMs) undergoing hematopoietic stem cell transplantation (HSCT). Pathophysiologically, IOL results in iron-induced toxicity in HSCT by producing reactive oxygen species (ROS), which leads to detrimental effects on hematopoiesis, clonal evolution, and immunosuppression. IOL, therefore, may have a negative impact on the clinical outcomes of HSCT. For patients at a higher risk of developing IOL before HSCT, it is necessary to monitor red blood cell transfusion units, serum ferritin (SF) levels and MRI image of organs, and initiate iron removal therapy as soon as possible. Iron chelating therapy (ICT) might be safe and efficient in the post-HSCT period. We provide an overview of results from experimental and clinical evidence on the current understanding of IOL in patients with HMs undergoing HSCT, involving the underlying pathophysiological and clinical impact of IOL, as well as the significance of iron reduction therapy.

Recent Advancements in Poor Graft Function Following Hematopoietic Stem Cell Transplantation

Poor graft function (PGF) is a life-threatening complication that occurs after transplantation and has a poor prognosis. With the rapid development of haploidentical hematopoietic stem cell transplantation, the pathogenesis of PGF has become an important issue. Studies of the pathogenesis of PGF have resulted in some success in CD34⁺-selected stem cell boosting. Mesenchymal stem cells, N-acetyl-l-cysteine, and eltrombopag have also been investigated as therapeutic strategies for PGF. However, predicting and preventing PGF remains challenging. Here, we propose that the seed, soil, and insect theories of aplastic anemia also apply to PGF; CD34⁺ cells are compared to seeds; the bone marrow microenvironment to soil; and virus infection, iron overload, and donor-specific anti-human leukocyte antigen antibodies to insects. From this perspective, we summarize the available information on the common risk factors of PGF, focusing on its potential mechanism. In addition, the safety and efficacy of new strategies for treating PGF are discussed to provide a foundation for preventing and treating this complex clinical problem.

Iron overload in the HCT patient: a review

Iron overload (IO) is common in hematologic malignancies and hemoglobinopathies, largely due to red cell transfusion burden. End-organ damage from IO occurs via reactive oxygen species-mediated pathways. The impact of pretransplant IO on hematopoietic cell transplant (HCT) morbidity and mortality remains contentious; studies have shown mixed results, possibly due to variability in study population and design, as well as markers of IO. Ferritin has served as a traditional circulating marker of total body IO, but liver iron content by MRI appears to be a better marker of end-organ involvement. Novel surrogate markers including hepcidin, marrow Prussian blue staining, and labile plasma iron levels may prove to be more specific for HCT complications. Posttransplant phlebotomy, chelation, or both in combination remains the mainstays of treatment, though may ultimately be supplanted by pretransplant or peri-transplant use of bone marrow maturation agents or targeted chelation at time of highest IO risk. This review discusses the pathophysiology of IO in hematologic disease, the evidence supporting and refuting its negative impact on HCT outcomes, as well as current and future therapies.

Body Weight Loss Before Allogeneic Hematopoietic Stem Cell Transplantation Predicts Survival Outcomes in Acute Leukemia Patients

Most acute leukemia patients receive consecutive intensive chemotherapy, which usually takes several months before allogeneic hematopoietic stem cell transplantation (allo-HCT). Intensive chemotherapy often induces gastrointestinal adverse events. These adverse events leave patients in a state of malnutrition, leading to a reduction in body weight. In this study, we analyzed the impact of body weight loss before allo-HCT on survival outcomes of acute leukemia patients (acute myeloid leukemia, acute lymphoid leukemia and mixed phenotype acute leukemia). A loss of body weight (LBW), which was a reduction of body weight from diagnosis or relapse to transplantation, was calculated in 182 acute leukemia patients who received first allo-HCT at our center between June 2006 and September 2019. A receiver operating characteristics curve for nonrelapse mortality (NRM) was plotted for defining the cut-off value of LBW. The cutoff value of LBW was defined as 13.2%. A higher LBW was significantly associated with inferior NRM and overall survival (OS) (2-year [2y] NRM 36.1% versus 11.5%, P = .0025; 2y-OS 39.9% versus 65.8%, P = .020). The adverse impact of LBW was also confirmed in multivariate analyses for NRM and OS (HR of NRM 2.74 [1.25-6.03], P = .0012; HR of OS 2.06 [1.00-3.07], P = .0049). The main cause of death included disease progression (n = 34) and infection (n = 35). Death cause by infection was more frequently observed in the high-LBW group (15 cases [35.7%] versus 20 cases [14.3%]; P = .0035). In addition, subgroup analyses based on a combination of the body mass index at diagnosis and LBW were performed. When the non-overweight-low LBW group (body mass index [BMI] ≤25 and LBW ≤13.2%) was used as a reference in multivariate analysis, the overweight-high LBW group (BMI >25 and LBW >13.2%) showed an increased risk of poor survival outcomes (HR of NRM 4.27 [95% confidence interval {CI}, 1.82-10.0], P < .001; HR of OS 1.93 [95%, CI 1.00-3.71], P = .050). High LBW was significantly associated with inferior survival outcomes, and the adverse effect of malnutrition might be greater than the favorable effect of the reduction in overweight.