Clinical Outcome of Autologous Hematopoietic Cell Transplantation in Adult Patients with Acute Myeloid Leukemia: Who May Benefit from Autologous Hematopoietic Cell Transplantation?

Wilms' tumor gene 1 in hematological malignancies: friend or foe?

Wilms' tumor gene 1 (WT1) is a transcription and post-translational factor that has a crucial role in the biological and pathological processes of several human malignancies. For hematological malignancies, WT1 overexpression or mutation has been found in leukemia and myelodysplastic syndrome. About 70-90% of acute myeloid leukemia patients showed WT1 overexpression, and 6-15% of patients carried WT1 mutations. WT1 has been widely regarded as a marker for monitoring minimal residual disease in acute myeloid leukemia. Many researchers were interested in developing WT1 targeting therapy. In this review, we summarized biological and pathological functions, correlation with other genes and clinical features, prognosis value and targeting therapy of WT1 in hematological features.

Autologous stem cell transplantation in adult patients with intermediate-risk acute myeloid leukemia in first complete remission and no detectable minimal residual disease. A comparative retrospective study with haploidentical transplants of the global committee and the ALWP of the EBMT

In patients with acute myeloid leukemia (AML) of intermediate-risk (IR) in first remission (CR1) with no measurable residual disease (MRD negative), the choice of the best consolidation is questionable. 1122 adult patients from 196 centers, transplanted in 2010-21 were analyzed: 547 received an autologous stem cell transplantation (ASCT) and 575 a Haploidentical donor transplant. Because of a significant interaction, comparisons were done separately for patients with wild-type FLT3 (FLT3-wt) and FLT3-ITD mutation (FLT3-ITD). In FLT3-wt patients, haploidentical transplants had two year lower relapse incidence (RI) (16.9% versus 32.6%; HR = 0.40, p < 0.001), higher NRM higher (17.2% vs 3.5%; HR = 7.02, p < 0.001), similar LFS (65.9% vs 63.8%; p = 0.37) and lower OS (73.2% vs 80.6%; HR = 1.69, p = 0.018). In FLT3-ITD patients, haploidentical transplants had two year lower RI (8.2% vs 47.8%; HR = 0.14, p < 0.001) higher NRM (20.2% vs 5.6%; HR = 3.43, p = 0.002), better LFS (71.5% vs 46.6%; HR = 0.53, p = 0.007) and similar OS (73.5% vs 61.9%; p = 0.44). In IR AML patients with FLT3-wt in MRD negative CR1, autologous stem cell transplantation is a valid option, while in patients with FLT3-ITD, haploidentical transplant is better. Whether autologous transplantation is superior to chemotherapy in FLT3-wt patients and the role of maintenance therapy with FLT3 inhibitors remain to be studied.

Outcome of autologous stem cell transplantation in patients with favorable-risk acute myeloid leukemia in first remission

OBJECTIVE

To evaluate the efficacy of autologous hematopoietic stem cell transplantation (auto-HSCT) in patients with favorable-risk acute myeloid leukemia in first remission.

METHOD

Twenty patients who received auto-HSCT at our center between January 2014 and January 2021 were retrospectively reviewed.

RESULTS

Until last follow-up, three patients in the cohort were dead due to relapse. The estimated 1-year and 5-year overall survival were 95.00% ± 4.87% and 83.82% ± 8.58%, respectively. The estimated 5-year RFS and CIR (cumulative incidence of relapse) were 85.00% ± 7.98% and 15.00% ±7.98%, respectively.

CONCLUSION

The outcome of auto-HSCT in patients with favorable-risk acute myeloid leukemia in first remission was excellent and auto-HSCT could be an effective treatment for these patients.

Risk stratification by 30-day prognostic factors of clinical outcomes after granulocyte transfusion in acute myeloid leukemia: A single-center retrospective study

Background

Granulocyte transfusions (GTs) have been used to treat infections in neutropenic patients undergoing chemotherapy or hematopoietic stem cell transplantation. However, there is persistent controversy regarding their outcomes. We aimed to analyze accumulated clinical and laboratory data from patients with acute myeloid leukemia (AML) who underwent GT at our institution in the last 10 years to determine optimal parameters to estimate the GT effect. We hypothesized that patients grouped according to prognostic factors would have inconsistent clinical outcomes.

Materials and methods

In this single-center retrospective study, we collected medical records of 219 GT-treated patients diagnosed with AML from 2009 to 2019. Prognostic factors, including clinical and laboratory parameters, were assessed. Serial measurements of laboratory parameters before and after GT were collected, and the area under the curve of the white blood cells (AUC-WBC) was calculated using the trapezoidal method. A prognostic scoring system using 8 factors from multivariate analysis was analyzed. The primary outcome was survival at 30 days (D30) after GT initiation.

Results

The 8 factors for the prognosis scoring system included secondary AML, mean AUC-WBC, prothrombin time, and levels of blood urea nitrogen (BUN), bilirubin, alanine aminotransferase (ALT), phosphorus, and lactate dehydrogenase (LDH). Patients were grouped into 4 risk groups (low, medium, high, and very high), and the D30 survival rates for each group were as follows: 87.6% (99/113), 55.9% (33/59), 21.1% (4/19), and 0% (0/19), respectively. Hematopoiesis, liver, and renal function affected the outcome. FLT3 mutation acted as a favorable factor for D30 survival.

Conclusions

GT response in patients with AML seemed to be reflected by 8 score markers, and GT was significantly effective in the low-risk group. We suggest that it is important to evaluate the risk assessment of patients before GT to achieve better outcomes.

Feasibility and efficacy of salvage allogeneic stem cell transplantation in AML patients relapsing after autologous stem cell transplantation

Autologous hematopoietic cell transplantation (HCT) is suitable for consolidation of favorable-/intermediate-risk AML patients in CR1. However, ~50% of AML patients relapse after autologous HCT, and efficacy of subsequent salvage strategies including allogeneic HCT remains unclear. We studied 123 consecutive patients with newly diagnosed AML undergoing high-dose chemotherapy (HDCT)/autologous HCT in CR1. In relapsing patients afterwards, we analyzed salvage treatments and outcomes focusing particularly on salvage allogeneic HCT. Of 123 patients, 64 (52%) relapsed after autologous HCT. Subsequently, 13 (21%) received palliative therapy, whereas 51 (79%) proceeded to salvage therapy with a curative intent. Of the 47 patients with a curative intent and who did not proceed directly to allogeneic HCT, 23 (49%) achieved CR2 or had ongoing hematologic CR1 despite molecular relapse. Finally, 30 patients (47%) received allogeneic HCT with estimated 3-year leukemia-free and overall survival rates of 33% and 43%. Hematologic remission at allogeneic HCT and lack of acute GvHD had a positive impact on OS and LFS (p < 0.05). Our study suggests that almost 80% of AML patients can undergo salvage therapy following relapse after front-line HDCT/autologous HCT. Allogeneic HCT can provide cure in one third of patients relapsing after front-line HDCT/autologous HCT.

History and Development of Autologous Stem Cell Transplantation for Acute Myeloid Leukemia

This review describes the development of cryopreservation, the birth of autologous stem cell transplantation (ASCT) and its past and present use to consolidate adult patients with acute myelogenous leukemia (AML). It summarizes the first autografts in patients in relapse, the experience of autografting in complete remission (CR), using bone marrow unpurged or purged in vitro with cyclophosphamide-derivatives, and the important shift to peripheral blood stem cells. The review also discusses the results of recent studies in favor of the use of ASCT to consolidate good- and intermediate-risk patients who reach CR with no detectable minimal residual disease, and those which support the inclusion of maintenance therapy post autograft with hypomethylating agents, anti-BCL-2, and, possibly, in the future, anti AML chimeric antigen receptor-T cells. Carefully applied to well-selected patients, ASCT may regain interest, because of its simplicity, its reduced toxicity, lower non-relapse mortality and better quality of life.

Prognostic values of D816V KIT mutation and peri-transplant CBFB-MYH11 MRD monitoring on acute myeloid leukemia with CBFB-MYH11

Given the controversies in the prognostic value of KIT mutations and optimal thresholds and time points of MRD monitoring for AML with CBFB-MYH11, we retrospectively evaluated 88 patients who underwent allogeneic hematopoietic stem cell transplantation (Allo-HSCT, n = 60) or autologous HSCT (Auto-HSCT, n = 28). The D816V KIT mutation was significantly associated with post-transplant relapse, contrasting with other types of mutations in KIT. Pre- and post-transplant (3 months after transplant) CBFB-MYH11 MRD assessments were useful in predicting post-transplant relapse and poor survival. The optimal threshold was determined as a 2 log reduction at both time points. In multivariate analysis, the D816V KIT mutation and CBFB-MYH11 MRD assessments were independently associated with post-transplant relapse and survival. Stratification by D816V KIT and pre-transplant CBFB-MYH11 MRD status further distinguished the risk of relapse and survival. Auto-HSCT was superior to Allo-HSCT in MRD negative patients without D816V KIT, while Allo-HSCT trended to be superior to Auto-HSCT in patients with MRD positivity or the D816V KIT mutation. In conclusion, this study demonstrated the differentiated prognostic value of the D816V KIT mutation in AML with CBFB-MYH11 and clarified optimal time points and thresholds for CBFB-MYH11 MRD monitoring in the setting of HSCT.

Autologous hematopoietic cell transplantation following high-dose cytarabine consolidation for core-binding factor-acute myeloid leukemia in first complete remission: a phase 2 prospective trial

Core-binding factor (CBF)-acute myeloid leukemia (AML) generally have a favorable prognosis. However, approximately 50% of patients experience disease relapse during or after post-remission therapy. Retrospective studies on autologous hematopoietic cell transplantation (AHCT) have shown improved survival with decreased relapse rate in CBF-AML. In this prospective study, we evaluate the outcomes of AHCT following high-dose cytarabine (HiDAC) consolidation in patients with CBF-AML in first complete remission (CR). Adult patients with CBF-AML achieving first CR after induction chemotherapy were eligible for the study. High-dose chemotherapy before AHCT included intravenous busulfan (3.2 mg/kg/day, days - 7 to - 5) and etoposide (400 mg/m²/day, days - 3 to - 2). Twenty-nine patients, 17 with t(8;21) and 12 with inv(16), underwent AHCT following 2 or 3 courses of HiDAC consolidation. The estimated 5-year overall and disease-free survival rates were between 89.0% and 82.5%, respectively. The cumulative incidences of relapse and non-relapse mortality were between 17.5% and 0%, respectively. Presence of measurable residual disease (MRD) before AHCT and KIT mutation were significantly associated with relapse after transplantation. In conclusion, the post-remission strategy of AHCT following HiDAC consolidation in CBF-AML was feasible and efficacious. Assays for MRD and KIT mutation may guide selection of patients who will benefit from AHCT in CBF-AML in first CR.

Long-Term Outcomes After Autologous Versus Allogeneic Stem Cell Transplantation in Molecularly-Stratified Patients With Intermediate Cytogenetic Risk Acute Myeloid Leukemia: A PETHEMA Study

Acute myeloid leukemia (AML) with intermediate risk cytogenetics (IRcyto) comprises a variety of biological entities with distinct mutational landscapes that translate into differential risks of relapse and prognosis. Optimal postremission therapy choice in this heterogeneous patient population is currently unsettled. In the current study, we compared outcomes in IRcyto AML recipients of autologous (autoSCT) (n = 312) or allogeneic stem cell transplantation (alloSCT) (n = 279) in first complete remission (CR1). Molecular risk was defined based on CEBPA, NPM1, and FLT3-ITD mutational status, per European LeukemiaNet 2017 criteria. Five-year overall survival (OS) in patients with favorable molecular risk (FRmol) was 62% (95% confidence interval [CI], 50-72) after autoSCT and 66% (95% CI, 41-83) after matched sibling donor (MSD) alloSCT (P = .68). For patients of intermediate molecular risk (IRmol), MSD alloSCT was associated with lower cumulative incidence of relapse (P < .001), as well as with increased nonrelapse mortality (P = .01), as compared to autoSCT. The 5-year OS was 47% (95% CI, 34-58) after autoSCT and 70% (95% CI, 59-79) after MSD alloSCT (P = .02) in this patient subgroup. In a propensity-score matched IRmol subcohort (n = 106), MSD alloSCT was associated with superior leukemia-free survival (hazard ratio [HR] 0.33, P = .004) and increased OS in patients alive 1 year after transplantation (HR 0.20, P = .004). These results indicate that, within IRcyto AML in CR1, autoSCT may be a valid option for FRmol patients, whereas MSD alloSCT should be the preferred postremission strategy in IRmol patients.

Comparison of post-remission strategies in acute myeloid leukemia: Autologous hematopoietic stem cell transplantation versus consolidation chemotherapy

Autologous Hematopoietic Stem Cell Transplantation (auto-HSCT) has become a therapeutic option for first-line consolidation in Acute Myeloid Leukemia (AML) patients with favorable and intermediate risk features. A total of 101 AML patients in first complete remission, who were not eligible for allogeneic HSCT, were randomized to receive intensive cytarabine-based chemotherapy or to undergo auto-HSCT. The probability of LFS was significantly better in auto-HSCT recipients compared to chemotherapy arm (43% vs 4.8%, p=0.008). At the end of 915 (30-4470) days of followup, the probability of overall survival was better in auto-HSCT group compared to chemotherapy, without statistical significance (79.2% vs 38.8%, p=0.054). Multivariate analysis revealed a significant predictive impact of cytogenetic risk status on OS (p=0.002, HR: 2.824, 95% CI: 1.445-5.521). Auto-HSCT is considered as an effective consolidation approach in favorable and intermadiate risk AML patients.

Postremission therapy with repeated courses of high-dose cytarabine, idarubicin, and limited autologous stem cell support achieves a very good long-term outcome in European leukemia net favorable and intermediate-risk acute myeloid leukemia

Consolidation treatment in acute myeloid leukemia (AML) patients achieving complete remission (CR) is warranted. High-dose cytarabine (HDAC) is considered first choice in favorable risk and an option in intermediate-risk AML. However, its optimal dose and schedule, as well as the benefit of additional chemotherapy agents remain controversial. Herein, we report on the long-term outcome of consecutive unselected AML patients treated with repeated courses of HDAC, with the addition of idarubicin, followed by autologous peripheral blood stem cell (PBSC) support, in order to limit toxicity, according to Northern Italy Leukemia Group (NILG) AML-01/00 study (EUDRACT number 00400673). Among 338 patients consecutively diagnosed from 2001 to 2017 at our center, 148 with high-risk AML (adverse cytogenetic, isolated FLT3-internal tandem duplication mutation, refractory to first induction) were addressed to allogeneic stem cell transplant. All other cases, 186 patients (55%), median age 53 (range 19-75), were considered standard-risk and received the NILG AML-01/00 program. After achieving CR, patients were mobilized with cytarabine 8 g/sqm to collect autologous CD34+-PBSC and received three consolidation cycles with HDAC (20 g/sqm) plus idarubicin (20 mg/sqm) per cycle, followed by reinfusion of limited doses of CD34+ PBSC (1-2x106/kg). The program was completed by 160 (86%) patients. Toxicity was acceptable. Neutrophils recovered a median of 10 days. Treatment-related mortality was 3/160 (1.8%). After a median follow-up of 66.4 months, overall survival (OS) and relapse-free survival (RFS) at 5-years were 61.4% and 52.4%, respectively. Twenty-eight selected patients aged >65 had similar outcomes. According to European leukemia net-2010 classification, the OS and RFS at 5-years were 76.4% and 65% in favorable risk, without differences between molecular subgroups, 52.3% and 47.2% in Intermediate-I, 45.2% and 36.5% in Intermediate-II risk patients, respectively. In conclusion, consolidation including repeated courses of high dose cytarabine and idarubicin, with limited PBSC support, proved feasible and very effective in nonhigh risk patients. The incorporation of novel agents in its backbone may be tested to further improve patient's prognosis.

The Role of Measurable Residual Disease (MRD) in Hematopoietic Stem Cell Transplantation for Hematological Malignancies Focusing on Acute Leukemia

The significance of measurable residual disease (MRD) in hematopoietic stem cell transplantation (HSCT) is well recognized in different hematological malignancies, but the evidence indicate that pre-transplant MRD status is of particular importance in acute lymphoblastic leukemia (ALL) and acute myeloid leukemia (AML). In ALL, inadequate response at the level of MRD is a commonly accepted risk factor for relapse and thus an indication for allogeneic HSCT. Similarly, growing evidence from the literature strongly suggest that MRD detected by multiparameter flow cytometry or molecular techniques should be also used for risk stratification in AML at the time of HSCT. Despite the well-defined association of MRD and outcomes of HSCT in acute leukemias, there are still many open issues such as the role of additional pre-transplant consolidation for MRD eradication, the ability of HSCT to overcome negative influence of MRD positivity on survival, the impact of conditioning regimen intensity on MRD clearance post HSCT, and transplantation outcomes or the selection of optimal donor with regards to MRD status. In addition, the role of MRD assessment in guiding post-transplant maintenance treatment should also be addressed in prospective trials. These open issues mostly awaiting further clinical studies will be discussed in our current review.

Outcomes of Autologous Hematopoietic Cell Transplantation Compared With Chemotherapy Consolidation Alone for Non-High-Risk Acute Myeloid Leukemia in First Complete Remission in a Minority-Rich Inner-City Cohort With Limited Access to Allografts

INTRODUCTION

In the United States, autologous hematopoietic cell transplantation (autoHCT) has fallen out of favor over chemotherapy consolidation for non-high-risk acute myeloid leukemia (AML) when allogeneic hematopoietic cell transplantation (alloHCT) is unfeasible, which is common in racial minorities because of donor registry under-representation and socioeconomic challenges. We compared autoHCT consolidation outcomes with chemotherapy alone in a minority-rich cohort in the Bronx.

PATIENTS AND METHODS

We identified adults with favorable or intermediate cytogenetic risk AML in first complete remission after induction at Montefiore Medical Center from 1999 to 2015, and analyzed 81 patients who received consolidation with ≥2 cycles of chemotherapy, of whom 28 received autoHCT.

RESULTS

The cohort predominantly consisted of ethnic/racial minorities (69%). Age, sex, race, presenting white cell count, and cytogenetic risk were similar between groups. The autoHCT group had longer relapse-free (RFS; 43 vs. 11 months; P = .003) and overall (OS) survival (not reached vs. 36 months; P = .043). Adjusted multivariable analysis showed significant benefit of autoHCT over chemotherapy alone for RFS (hazard ratio [HR], 0.53; 95% confidence interval [CI], 0.37-0.75; P < .001) and OS (HR, 0.61; 95% CI, 0.40-0.95; P = .027).

CONCLUSION

In this inner-city non-high-risk AML cohort, autoHCT provided OS and RFS benefit compared with chemotherapy alone. AutoHCT might constitute a valuable option for ethnic/racial minorities affected by significant barriers to alloHCT, whereas integration of measurable residual disease can help select patients more likely to benefit.

Autologous Hematopoietic Stem Cell Transplantation in Acute Myelogenous Leukemia

The clinical outcomes of autologous hematopoietic stem cell transplantation (ASCT) in acute myelogenous leukemia (AML) have improved over time. Indeed, numerous studies have demonstrated that ASCT is associated with a lower relapse rate and acceptable nonrelapse mortality compared with chemotherapy alone in patients with AML. In addition, ASCT is also associated with comparable overall survival outcomes to those of allogeneic hematopoietic stem cell transplantation in some patients with AML. To date, age, cytogenetic and molecular risk stratification, and minimal residual disease (MRD) status have been shown to be closely related to clinical outcomes following ASCT. ASCT is recommended for patients with favorable-risk and intermediate-risk AML in first complete remission and patients with acute promyelocytic leukemia in second complete remission for whom a matched sibling donor is not available. MRD status pre-ASCT is the most important factor to consider when determining whether a patient is eligible for ASCT and can effectively predict clinical outcomes after ASCT. Advanced age is not an absolute contradiction for ASCT. In this review, we describe the literature and clinical trials evaluating the outcomes of ASCT in patients with AML and discuss the indications for ASCT therapy. Because the greatest concern in ASCT recipients is early relapse, important factors that should be monitored before ASCT and future perspectives in this area are also presented.

Prognostic Prediction Model for Second Allogeneic Stem-Cell Transplantation in Patients With Relapsed Acute Myeloid Leukemia: Single-Center Report

PURPOSE

To identify factors affecting survival outcomes and to develop a prognostic model for second allogeneic stem-cell transplantation (allo-SCT2) for relapsed acute myeloid leukemia (AML) after the first autologous or allogeneic stem-cell transplantation.

PATIENTS AND METHODS

Seventy-eight consecutive adult AML patients who received allo-SCT2 were analyzed in this retrospective study.

RESULTS

The 4-year overall survival (OS) rate was 28.7%. In multivariate analysis, poor cytogenetic risk at diagnosis, circulating blast ≥ 20% at relapse, duration from first transplantation to relapse < 9 months, and failure to achieve morphologic complete remission after allo-SCT2 were factors associated with poor OS. A prognostic model was developed with the following score system: intermediate and poor cytogenetic risk at diagnosis (0.5 and 1 point), peripheral blast ≥ 20% at relapse (1 point), duration from the first transplantation to relapse < 9 months (1 point), and failure to achieve morphologic complete remission after allo-SCT2 (1 point). The model identified 2 subgroups according to the 4-year OS rate: 51.3% in the low-risk group (score < 2) and 2.8% in the high-risk group (score ≥ 2) (P < .001).

CONCLUSION

This prognostic model might be useful to make an appropriate decision for allo-SCT2 in relapsed AML after the first autologous or allogeneic stem-cell transplantation.

Comparison of the effects of early intensified induction chemotherapy and standard 3+7 chemotherapy in adult patients with acute myeloid leukemia

BACKGROUND

Standard remission induction chemotherapy consisting of anthracycline plus cytarabine (3+7) is administered for adult acute myeloid leukemia (AML). However, the effects of intensified regimen on complete remission (CR), relapse and overall survival (OS) remain unknown.

METHODS

We analyzed 1195 patients treated with idarubicin plus cytarabine/BHAC (3+7) from 2002 to 2013. Among them, 731 received early intensification with 3-day cytarabine/BHAC (3+10, N=363) or 2-day idarubicin plus cytarabine/BHAC 3 days (5+10, N=368). The 3+10 and 5+10 strategies were applied to patients with bone marrow blast counts of 5-20% and >20% on day 7 of 3+7, respectively.

RESULTS

Early intensification correlated with a younger age (median: 40 vs. 45 yr) and higher t(8;21) frequency (20.4% vs. 7.1%), compared to 3+7. After early intensification, the early death rates were higher among the elderly (3+10 [15.7%], 5+10 [21.7%] vs. 3+7 [6.3%], P=0.038), while the post-induction CR rate was higher in young patients (3+10 [79.8%], 5+10 [75.1%] vs. 3+7 [65.1%], P<0.001). Early relapse rate was also decreased (3+10 [11.8%], 5+10 [11.7%] vs. 3+7 [22.0%], P<0.001). In multivariate analysis, early intensification correlated with an inferior 5-year OS among elderly patients (19.2% vs. 22.8%; hazard ratio [HR]=1.84, 95% confidence interval [CI]; 1.11-3.06, P=0.018) and lower overall relapse rate among young patients (33.0% vs. 41.4%, P=0.023; HR=0.71, 95% CI; 0.55-0.93, P=0.012).

CONCLUSION

Early intensification correlated with higher CR and lower relapse rates, but not OS in young AML patients. In elderly patients, early intensification correlated with a higher early death rate and poorer OS.