Autologous stem cell transplantation using modified TAM or combination of triple-alkylating agents conditioning regimens as one of the post-remission treatments in patients with adult acute myeloid leukemia in first complete remission

Long-term clinical outcomes of hematopoietic cell transplantation for intermediate-to-poor-risk acute myeloid leukemia during first remission according to available donor types

Standard therapy for acute myeloid leukemia (AML) consists of hematopoietic cell transplantation (HCT) including autologous-HCT (AUTO) and allogeneic-HCT from a matched-sibling donor (MSD) or well-matched unrelated donor (WM-URD). When a conventional donor is not available, HCT from a partially-matched (PM)-URD or familial-mismatched donor (FMMD) is typically considered. We analyzed 561 patients with intermediate to poor-risk molecular cytogenetics who underwent transplant from 2002 to 2013 in their first remission. Engraftment was successful in all donor types except five patients who died in aplasia. Disease-free survival (DFS) at 5 years was 61.4% for MSD, 62.1% for WM-URD, 65.3% for FMMD, 44.7% for AUTO and 36.8% for PM-URD. AUTO showed the highest relapse rate (51.0%) compared to MSD (23.5%) and FMMD (18.5%), but showed the lowest 5-year non-relapse mortality (NRM) rate (3.8%). PM-URD showed the highest NRM (29.3%) with more instances of acute graft-vs.-host disease (GVHD) with grade≥III (29.3%), compared to MSD (15.6%) and FMMD (15.7%). In a poor-risk subgroup, the 5-year DFS for FMMD and MSD was 59.8% and 46.7%, respectively, while for AUTO and PM-URD it was 12.6% and 0.0%, respectively, which was caused by a high relapse rate (87.1% in AUTO, 83.3% in PM-URD). In the intermediate-risk subgroup, the 5-year DFS of AUTO (53.9% was not different from the conventional donors in multivariate analysis, presenting a low NRM rate (5.1%). FMMD should be considered prior to PM-URD in intermediate-to-poor-risk AML and GVHD prophylaxis should be intensified when PM-URD is needed. AUTO might be considered for selected patients in the intermediate-risk group.

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.

Quantitative fragment analysis of FLT3-ITD efficiently identifying poor prognostic group with high mutant allele burden or long ITD length

Mutation of the fms-like tyrosine kinase 3-internal tandem duplication (FLT3-ITD), which is one of the most frequent genetic alterations, strongly contributes to an increased risk of treatment failure and to poor prognosis. In this study, we established quantitative fragment analysis of FLT3-ITD simultaneously measuring mutant allele burden and length, verified the analytical performance and evaluated the clinical significance in adult acute myeloid leukemia (AML) patients. FLT3-ITD was detected in 73 of 363 adult AML patients (20.1%) and high mutant allelic burden (⩾50%, n=13) and long ITD length (⩾70 base pairs, n=15) were significantly associated with inferior overall survival (OS; P=0.002 and 0.005, respectively) and event-free survival (EFS; P=0.004 and 0.007, respectively). FLT3-ITD poor prognostic group was identified as patients with high allele burden or long ITD length (n=24), which revealed significant adverse clinical outcome for both OS (P<0.001) and EFS (P<0.001). In cytogenetically normal AML, even FLT3-ITD low allele burden and short length was associated with poorer OS (P=0.037) and EFS (P=0.044) than wild type, whose influence was overcome when hematopoietic stem cell transplantation was performed. In minimal residual disease monitoring, FLT3-ITD negativity after consolidation therapy was a valuable predictor of better OS (P<0.001) and EFS (P<0.001). FLT3-ITD poor prognostic group with high mutant allele burden or long ITD length is efficiently identified by quantitative fragment analysis.

Outcome of allogeneic hematopoietic stem cell transplantation for cytogenetically normal AML and identification of high-risk subgroup using WT1 expression in association with NPM1 and FLT3-ITD mutations

According to recent guidelines, cytogenetically normal acute myeloid leukemia (CN AML) is divided into four molecular subgroups based on nucleophosmin-1 (NPM1) and FMS-like tyrosine kinase 3-internal tandem duplication (FLT3-ITD) mutations. All subgroups except for isolated NPM1mut are associated with poor prognosis. We retrospectively analyzed 223 patients with CN AML, 156 of whom were treated with standard chemotherapy. For postremission therapy, patients with available donors underwent allogeneic (allo) hematopoietic stem cell transplantation (HSCT) and the rest were treated with autologous HSCT or chemotherapy alone. We first compared the 4 conventional molecular subgroups, and then created another 4 subgroups based on WT1 expression: isolated NPM1mut, NPM1wt/FLT3-ITD-neg with low WT1 or high WT1, and FLT3-ITD-pos CN AML. We finally evaluated 89 patients who were treated with allo HSCT and achieved complete remission after standard chemotherapy. FLT3-ITD CN AML showed the worst outcome irrespective of NPM1mut, and isolated NPM1mut CN AML showed no significant differences compared with NPM1wt/FLT3-ITD-neg CN AML. In contrast, two newly stratified low-risk subgroups (NPM1wt/FLT3-ITD-neg with low WT1 and isolated NPM1mut CN AML) showed higher remission rates with superior overall survival (OS) compared with the other two high-risk subgroups, which showed a higher relapse rate even after allo HSCT. Further analysis showed that higher pre-HSCT expression of WT1 resulted in a higher relapse rate and poorer OS after allo HSCT. For CN AML, a risk-adapted approach using allo HSCT with novel agents should be evaluated with stratification specified by WT1. © 2015 Wiley Periodicals, Inc.

Equivalent outcome of autologous stem cell transplantation and reduced intensity conditioning stem cell transplantation in acute myeloid leukemia patients with t(8;21)

We analyzed the outcome of stem cell transplantation (SCT) for 59 acute myeloid leukemia (AML) patients with t(8;21). The 5-year overall and disease-free survival (OS and DFS) were 70.2 and 68.4%, respectively. The 5-year cumulative incidence of relapse (CIR) and nonrelapse mortality were 16.9 and 13.6%, respectively. OS and DFS in the reduced-intensity conditioning (RIC)-SCT group (70.4%) were not different from in the autologous SCT (ASCT) group (72.4 and 69.0%, respectively). Age was a factor affecting OS (p = 0.007) and DFS (p = 0.008) in the ASCT group, but not in the RIC-SCT group. In the ASCT group, lack of the X chromosome (-X) and an age of >50 years were associated with inferior survival; however, these differences disappeared in the RIC-SCT group. CIR was significantly higher in patients with -X than in those without -X only in the ASCT group (p = 0.038), i.e. not in the RIC-SCT group. ASCT and RIC-SCT are equally effective for the intensification of postremission treatment of AML patients with t(8;21). The subgroups with advanced age or -X should be preferentially considered for RIC-SCT, rather than ASCT. Further investigations with randomized prospective trials of a sizeable study population are warranted.

Conditioning regimens in acute myeloid leukemia

Current intensive consolidation chemotherapy for patients with acute myeloid leukemia (AML) produces median remission duration of 12-18 months, with less than 30% of patients surviving 5 years free of disease. Post-remission therapy is necessary to prevent relapse in most patients with AML; therefore, the aim of post-remission treatment is to eradicate the minimal residual disease. Nevertheless, the optimal form of treatment is still under debate. The choice among the possible approaches (intensive chemotherapy, autologous or allogeneic hematopoietic stem cell transplantation) relies on two main factors: the expected risk of relapse, as determined by biological features, and expected morbidity and mortality associated with a specific option. In this review, we focus on the different preparative regimens before autologous and allogeneic hematopoietic stem cell transplantation in patients with AML, stressing the importance of an adequate conditioning regimen as a mandatory element of a successful AML therapy, in both the allogeneic and the autologous transplant setting.

Combinatorial molecular marker assays of WT1, survivin, and TERT at initial diagnosis of adult acute myeloid leukemia

High levels of expression of Wilms' tumor gene 1 (WT1), survivin, or telomerase reverse transcriptase (TERT) genes are introduced as leukemia-associated targets predicting clinical outcome. We prospectively investigated the leukemia-associated gene transcripts by real-time quantitative polymerase chain reaction from 151 adult patients with AML associated with the patients' clinical characteristics. The maximum levels of each gene in bone marrow were 64.4-, 8.1-, and 3.9-fold higher than those in the normal control, respectively. In contrast to the WT1 and TERT levels, survivin showed comparatively higher expression in the unfavorable cytogenetic group of patients. We found a significant difference in survivin levels between the CR and non-CR groups (P = 0.0237). TERT expression levels were higher in patients who had a greater number of peripheral blood leukemic blasts at diagnosis (P = 0.0191). Non-MRC subtypes and patients without specific mutations were the most powerful predictive factors for a better CR rate, by multivariate analyses. The lower levels of both WT1 and survivin co-expression (P = 0.0129) and both survivin + TERT co-expression (P = 0.0115) were significant factors for better OS. Besides lower initial levels of serum ferritin (P = 0.0401), lower levels of WT1 (P = 0.0438) and survivin (P = 0.0401), lower levels of both WT1 and survivin co-expression (P = 0.0031), and the three-gene combination of lower WT1 + survivin + TERT (P = 0.0454) were powerful predictive factors for better EFS. As our findings were based on a single disease entity, that is, adult AML, they suggest that the expression of these genes may be critical for the immunobiology of AML to influence the clinical outcome in various ways.

Experiences of t-PA use in moderate-to-severe hepatic veno-occlusive disease after hematopoietic SCT: is it still reasonable to use t-PA?

Hepatic veno-occlusive disease (VOD) remains one of the most severe complications of hematopoietic SCT (HSCT). Anticoagulation and thrombolytic therapies using tissue-plasminogen activator (t-PA) have been used, but are reported to be ineffective and are associated with significant bleeding complications. We analyzed 56 moderate-to-severe post HSCT hepatic VOD cases treated with t-PA. We analyzed clinical outcomes according to the maximal daily dose of t-PA (t-PAmax) and the severity of VOD. Patients were stratified by t-PAmax10 mg (n=37) vs t-PAmax>10 mg (n=19). A higher t-PAmax was associated with increased mortality. Bleeding complications were more likely at higher t-PAmax in both moderate and severe VOD (P=0.036, 0.063), especially if patients had concomitant use of anticoagulants (36.4% vs 13.3%). In moderate VOD, the response rate was 86.4% for t-PAmax10 mg/day and 80% for t-PAmax>10 mg compared with 33.3% and 7.1%, respectively, for severe VOD (P=0.106). The 5-year OS in moderate and severe VOD was 49% and 7%, respectively, and it was 32% for t-PAmax10 mg and 18% for t-PAmax>10 mg. Our data demonstrate that lower bleeding complications and bleeding-related deaths may result from strict limitations on the t-PAmax without concomitant use of anticoagulation therapy. However, the overall response and survival outcomes should be re-evaluated by a well-validated study in the future.

BAALC and WT1 expressions from diagnosis to hematopoietic stem cell transplantation: consecutive monitoring in adult patients with core-binding-factor-positive AML

No consecutive analysis of BAALC and WT1 expressions associated with core-binding factor AML (CBF-AML) from diagnosis to hematopoietic stem cell transplantation (HSCT) has yet been reported. We investigated BAALC and WT1 expressions using a method of real-time quantitative polymerase chain reaction (RQ-PCR) at diagnosis, after induction chemotherapy, at pre-HSCT, and at post-HSCT period in 45 consecutive patients [t(8,21) (n = 28), inv(16) (n = 17)], who received HSCT as a post-remission treatment. BAALC and WT1 RQ-PCR decrement ratio (DR) was also calculated at post-induction chemotherapy, at pre-HSCT, and at post-HSCT compared with the diagnostic level. Higher BAALC expression at diagnosis showed significantly inferior OS (P = 0.031), EFS (P = 0.011), and higher CIR (P = 0.002) rates. At post-HSCT, both higher BAALC and WT1 expressions showed significantly inferior OS (P = 0.005, 0.016), EFS (P = 0.002, 0.006), and higher CIR (P = 0.001, 0.003) rates. A subgroup of t(8;21) showing higher BAALC and WT1 expressions at post-HSCT were also associated with inferior OS (P = 0.018, 0.015) and higher CIR rates (P = 0.019, 0.011). While BAALC DR showed no significant results on outcomes, WT1 DR more than 2-log at post-HSCT showed significantly lower CIR rate (P = 0.028). This study showed that higher post-HSCT BAALC and WT1 expressions in patients with CBF-AML may be good markers of minimal residual disease for the prediction of survival and relapse after HSCT.

Superior transplantation outcomes of 8/8-matched unrelated donors as well as matched siblings to autologous transplantation for acute myeloid leukemia with intermediate cytogenetics in first remission

OBJECTIVES

For patients with acute myeloid leukemia in first complete remission (AML CR1) lacking HLA-matched sibling donors (MSD), 8/8-matched unrelated donors (URD) are mostly used in cases with poor-risk features. For AML CR1 with intermediate cytogenetics, however, the benefit of 8/8-matched URD should be compared with non-allogeneic therapies as well as MSD.

METHODS

To address this issue, we assessed the transplantation outcomes of 8/8-matched URD (n = 54) compared with MSD (n = 145) or autologous transplantation (n = 89) for AML CR1 with intermediate cytogenetics.

RESULTS

In multivariate analyses, 8/8-matched URD had comparable 6-yr overall survival (OS, P = 0.997), disease-free survival (DFS, P = 0.951), and relapse (P = 0.672) to MSD, whereas 8/8-matched URD had a higher OS (P = 0.070) and DFS (P = 0.035) with lower relapse (P = 0.009) than autologous transplantation. No difference in non-relapse mortality was observed according to donor type. Notably, these equivalent or superior outcomes of 8/8-matched URD compared with MSD or autologous transplantation, respectively, were particularly evident in patients without poor-risk features (n = 200), such as older age, hyperleukocytosis at diagnosis, and myelodysplasia-related changes, who are not usual candidates for URD transplantation.

CONCLUSIONS

These results indicate that 8/8-matched URD are feasible next option in AML CR1 with intermediate cytogenetics, when lacking MSD, even in patients without poor-risk features.

The role of cytotoxic therapy with hematopoietic stem cell transplantation in the therapy of acute myelogenous leukemia in adults: an evidence-based review

Clinical research examining the role of hematopoietic stem cell transplantation (HSCT) in the therapy of acute myelogenous leukemia (AML) in adults is presented and critically evaluated in this systematic evidence-based review. Specific criteria were used for searching the published literature and for grading the quality and strength of the evidence and the strength of the treatment recommendations. Treatment recommendations based on the evidence are presented in Table 3, entitled Summary of Treatment Recommendations Made by the Expert Panel for Adult Acute Myelogenous Leukemia, and were reached unanimously by a panel of AML experts. The identified priority areas of needed future research in adult AML include: (1) What is the role of HSCT in treating patients with specific molecular markers (eg, FLT3, NPM1, CEBPA, BAALC, MLL, NRAS, etc.) especially in patients with normal cytogenetics? (2) What is the benefit of using HSCT to treat different cytogenetic subgroups? (3) What is the impact on survival outcomes of reduced intensity or nonmyeloablative versus conventional conditioning in older (>60 years) and intermediate (40-60 years) aged adults? (4) What is the impact on survival outcomes of unrelated donor HSCT vesus chemotherapy in younger (<40 years) adults with high risk disease?

Autologous stem cell transplantation using a modified TAM conditioning regimen for clinically aggressive non-Hodgkin's lymphoma

PURPOSE

High-dose chemotherapy (HDT) and autologous stem cell transplantation (ASCT) have been used for the treatment of clinically aggressive non-Hodgkin's lymphoma (NHL). However, the superiority of specific conditioning regimens has not yet been established. The present study evaluated the efficacy and toxicity of a conditioning regimen involving fractionated total body irradiation (TBI), and the use of Ara-C and melphalan (TAM) for clinically aggressive NHL.

MATERIALS AND METHODS

Between March 2002 and December 2004, 31 patients with aggressive NHL received fractionated TBI with a dose of 12 Gy over 3 days, and were administered 9 g/m(2) Ara-C and 100 mg/m(2) melphalan followed by autologous peripheral blood stem Cell Transplantation at the Catholic Hematopoietic Stem cell transplantation Center Korea. Patients that responded to first line chemotherapy and achieved complete remission (CR), or were in a first sensitive relapse were defined as having less advanced disease, while the other patients were defined as having more advanced disease.

RESULTS

Objective responses were obtained in 24 of 31 patients (77.4%), comprising complete remission in 19 patients (61.3%) and partial remission in 5 (16.1%) patients. The median follow-up time was 28 months (range 1 approximately 62 months). At 3 years, the overall survival and event-free survival (EFS) rates were 62.3% and 47.3%, respectively. Patients with less advanced disease and more advanced disease showed 3-year EFS rates of 73.3% and 22.5 %, respectively (p=0.006). Early (within the first 100 days) treatment-related mortality occurred in 3 (9.7%) patients. Of the 31 total patients, 15 (48.4%) developed grade 3 mucositis, 22 (70.9%) developed neutropenic fever, and two (6.5%) developed interstitial pneumonia syndrome>grade 3.

CONCLUSION

The modified TAM conditioning regimen and ASCT appear to be a feasible treatment regimen for clinically aggressive NHL, particularly for patients with less advanced disease.

Influential Factors for the Collection of Peripheral Blood Stem Cells and Engraftment in Acute Myeloid Leukemia Patients in First Complete Remission

Although several studies have investigated factors influencing peripheral blood stem cell (PBSC) mobilization in patients with nonmyeloid malignancies in an effort to increase the efficiency of autologous PBSC transplantation (APBSCT), there are very few reports on the efficiency of PBSC mobilization in patients with leukemia. We analyzed the effects of influential variables on successful mobilization and the correlation between infused cell doses and engraftment in acute myeloid leukemia (AML) patients in first complete remission (CR1) who received APBSCT. Between May 1998 and May 2003, 34 patients with AML underwent APBSC collections at our institution. All patients were in CR1 at the time of transplantation. Except for 1 patient, all patients successfully achieved the target CD34(+) cell yield of > or = 2 x 10(6)/kg. Among progenitor cells, the CD34(+) cell dose and the colony-forming unit-granulocyte-macrophage count showed significant correlations with neutrophil and platelet engraftments. The time to neutrophil engraftment was inversely correlated to the number of infused CD34(+) cells (r = -0.67; P < .001), whereas the time to neutrophil engraftment was not significantly correlated with the number of monocytes (r = 0.20; P = .701) or the number of nucleated cells (r = 0.35; P = .062). The time to platelet engraftment was significantly correlated with the dose of infused CD34(+) cells (r = -0.47; P = .012). The univariate analysis showed that more CD34(+) cells per kilogram and more CD34(+) cells per kilogram per day were collected from patients who had a shorter interval (less than 2 months) between diagnosis and PBSC harvest (P = .0111). In conclusion, this study showed that the CD34(+) cell dose was most strongly correlated with a successful engraftment in AML CR1 patients who underwent APBSCT. The proper timing of PBSC collections should be explored to optimize the outcome of APBSCT in AML CR1 patients.