ELN risk stratification and outcomes in secondary and therapy-related AML patients consolidated with allogeneic stem cell transplantation

Autologous or Allogeneic Hematopoietic Stem Cell Transplantation as Front-Line Treatment for Adult Secondary Acute Myeloid Leukemia Patients: The PETHEMA Registry Experience

It is widely accepted that allogeneic hematopoietic stem cell transplantation (allo-HSCT) is the sole potentially curative option available for secondary acute myeloid leukemia (sAML). However, clinical factors impacting outcomes after allo-HSCT and the potential role of autologous HSCT (auto-HSCT) in real-life series are needed. Previously, the PETHEMA group reported a series of 2310 patients with sAML in the nationwide registry. Of these, 876 were candidates to receive chemotherapy and 274 underwent HSCT (55 auto-HSCT and 219 allo-HSCT). In this study, we analyzed the role of auto-HSCT or allo-HSCT as front-line treatment for sAML patients included in the Spanish PETHEMA AML registry. Here we report an analysis of outcomes as well as prognostic variables in this series of patients undergoing auto-HSCT or allo-HSCT as part of the front-line treatment for sAML. We used the multinational PETHEMA AML registry (Clincial Trials.gov identifier NCT02607059) to identify adult patients (age ≥18 years) with a diagnosis of sAML who underwent auto- or allo-HSCT as front-line treatment in Spanish and Portuguese institutions between August, 1, 1992, and July, 31, 2020. Patient characteristics, diagnostic findings, and management, including treatments, characteristics of HSCT, and outcomes, were retrieved from the PETHEMA AML registry in this retrospective multicenter analysis. With a median follow-up of 32.7 months, better 5-year overall survival (OS) and leukemia-free survival (LFS) were obtained with allo-HSCT in first complete response (CR) (44.5% and 39.9%, respectively) compared with auto-HSCT in CR1 (30% and 20.5%, respectively) but without reaching statistical differences for OS (P = .22 and .03, respectively). The higher incidence of relapse in auto-HSCT is counterbalanced with the significantly lower nonrelapse mortality rate. For allo-HSCT recipients, 5-year outcomes were significantly influenced by the cytogenetic/genetic risk. In multivariate analysis, the adverse cytogenetic/genetic risk group retained statistical significance for all endpoints. We confirmed the role of allo-HSCT as a potential curative option for patients and report that auto-HSCT in CR can still provide a 5-year LFS of 20% in sAML patients. Finally, our results confirm adverse cytogenetic/genetic risk category as an independent negative factor in sAML patients undergoing HSCT.

Validation of the revised 2022 European LeukemiaNet risk stratification in adult patients with acute myeloid leukemia

ABSTRACT

In 2022, the European LeukemiaNet (ELN) risk stratification for patients with acute myeloid leukemia (AML) has been updated. We aimed to validate the prognostic value of the 2022 ELN classification (ELN22) by evaluating 1570 patients with newly diagnosed AML (median age, 56 years) treated with cytarabine-based intensive chemotherapy regimens. Compared with 2017 ELN classification (ELN17), which allocated 595 (38%), 413 (26%), and 562 patients (36%) to the favorable-, intermediate-, and adverse-risk categories, ELN22 classified 575 (37%), 410 (26%), and 585 patients (37%) as favorable, intermediate, and adverse risk, respectively. Risk group allocation was revised in 340 patients (22%). Most patients were reclassified into the ELN22 intermediate- or ELN22 adverse-risk group. The allocation of patients according to the ELN22 risk categories resulted in a significantly distinct event-free survival (EFS), relapse-free survival, and overall survival (OS). Compared with ELN17, reallocation according to the ELN22 recommendations resulted in a significantly improved prognostic discrimination for OS (3-year area under the curve, 0.71 vs 0.67). In patients with ELN22 favorable-risk AML, co-occurring myelodysplasia-related (MR) gene mutations did not significantly affect outcomes. Within the ELN22 adverse-risk group, we observed marked survival differences across mutational groups (5-year OS rate of 21% and 3% in patients with MR gene mutations and TP53 mutations, respectively). In patients harboring MR gene mutations, EZH2-, STAG2-, and ZRSR2-mutated patients showed an intermediate-like OS. In patients with secondary AML and those who underwent allogeneic hematopoietic cell transplantation, EFS and OS significantly differed between ELN22 risk groups, whereas the prognostic abilities of ELN17 and ELN22 classifications were similar. In conclusion, ELN22 improves prognostic discrimination in a large cohort of intensively treated patients with AML. Given the heterogeneous outcome in patients with MR gene alterations, ranging between those of intermediate and adverse risk patients, we suggest re-evaluation of risk allocation in these patients.

Clinical features and prognostic nomogram for therapy-related acute myeloid leukemia after allogeneic hematopoietic stem cell transplantation

Therapy-related acute myeloid leukemia (t-AML), which develops after cytotoxic therapy, has a poorer prognosis. Although allogeneic hematopoietic stem cell transplantation (allo-HSCT) is a potential cure, its efficacy varies among patients. In this retrospective study, we analyzed 154 patients with t-AML who underwent hematopoietic stem cell transplantation (HSCT) at our institution to determine their clinical characteristics and develop a prognostic nomogram. The median ages at t-AML diagnosis prior disease diagnosis was 42 and 39 years, respectively. Multivariate analysis identified key prognostic indicators: leukocyte count at AML diagnosis ≥7 × 10^9/L, genetic abnormalities before HSCT, platelet engraftment ≥28 days, age at prior disease ≥45 years, and relapse of prior disease. We developed a prognostic nomogram for LGPAR by categorizing patients into low, medium, and high-risk groups. The 3-year and 5-year overall survival (OS) rates for these groups were 92.6 %, 84.4 %, 14 %, and 92.6 %, 76.6 %, and 7 %, respectively. The 3-year and 5-year relapse-free survival (RFS) rates were 80 %, 75.9 %, 10.7 % and 80 %, 72.6 %, and 10.7 % for the respective risk groups. The 3-year and 5-year non-relapse mortality (NRM) rates were 0 %, 5.6 %, 63.3 % and 0 %, 9.3 %, and 63.3 % for these groups, respectively. This novel prognostic nomogram culminates in the development of a clinical decision-support tool for patients with t-AML undergoing allo-HSCT.

Allogeneic hematopoietic cell transplantation for therapy-related myeloid neoplasms arising following treatment for multiple myeloma: a retrospective study on behalf of the Chronic Malignancies Working Party of the EBMT

Therapy-related myeloid neoplasms (t-MN) are a complication of multiple myeloma (MM) treatment. Our retrospective, EBMT registry study included 157 such patients allografted (allo-HCT) between 2006 and 2018. Most patients (130) had a prior autologous HCT. Fifty-seven (36.4%) were transplanted for t-AML and 100 (63.6%) for t-MDS. Median times from MM and t-MN diagnoses to allo-HCT were 72.6 (interquartile range (IQR), 46.1-102.9) and 6.4 (IQR, 3.9-9.4) months. Fifty-eight (38.4%) t-MN patients were in complete remission (CR) at allo-HCT predominantly conditioned with reduced intensity (70.3%). With a median follow-up of 64.9 (95% CI: 39-76) months, relapse incidence (RI) from MM at 1 and 5 years was 4% (0-10%) and 12% (2-22%), respectively, with few deaths (n = 3) only due to MM disease progression, whereas t-MN RI and non-relapse mortality (NRM) at 1 and 5 years were 35% (95% CI 28-43%) and 45% (95% CI: 36-53%) and 20% (95% CI 13-26%) and 31% (95% CI: 23-39%). Overall survival (OS) and progression-free survival (PFS) estimates at 1 and 5 years were 55% (95% CI: 47-63%) and 27% (95% CI: 19-35%) and 45% (95% CI 36-53%) and 24% (95% CI 16-32%). Older (>65 years) t-MN patients with high-risk cytogenetics do not benefit from allo-HCT.

How we manage multiple myeloma with clonal hematopoiesis of indeterminate potential (CHIP): a case report

Background

Clonal hematopoiesis of indeterminate potential (CHIP) is characterized by genetic alterations associated with hematologic neoplasms, posing clinical challenges in managing concurrent hematological malignancies. CHIP may complicate the treatment landscape due to its potential to influence disease progression and treatment response. We report a 73-year-old male with multiple myeloma (MM) harboring a CHIP PPM1D mutation, elucidating the complexities and therapeutic considerations in such cases.

Case Description

After four cycles of cyclophosphamide, bortezomib, and dexamethasone therapy, he achieved a partial response, followed by complete hematologic response (CR) post eight cycles of lenalidomide, dexamethasone, and bortezomib therapy. Despite this, upfront autologous hematopoietic stem cell transplantation (HSCT) was initially deemed unsuitable due to positive PPM1D CHIP status. HSCT proceeded after aggressive relapse with clonal evolution but yielded short-lived response. Following failure of >4 lines of therapy, he received chimeric antigen receptor T (CAR-T) cell therapy (ciltacabtagene autoleucel) for salvage. This approach successfully induced remission, which was maintained for 6 months.

Conclusions

This case report highlights MM management complexities in CHIP presence, suggesting potential utility of HSCT and CAR-T cell therapy. Prospective studies are necessary to evaluate the safety and efficacy of these therapies in myeloma patients with concurrent CHIP, aiming to optimize treatment strategies and improve outcomes in this challenging clinical context.

Therapy-related AML: long-term outcome in a large cohort of AML-patients with intensive and non-intensive therapy

Therapy-related acute myeloid leukemia (t-AML) often exhibits adverse (genetic) features. There is ongoing discussion on the impact of t-AML on long-term outcome in AML. Therefore, we retrospectively analyzed clinical and biological characteristics of 1133 AML patients (225 t-AML patients and 908 de novo AML patients) with a median follow-up of 81.8 months. T-AML patients showed more adverse genetic alterations, higher age and more comorbidities as compared to de novo AML. Median OS in intensively treated t-AML patients was 13.7 months as compared to 39.4 months in de novo AML (p < 0.001). With non-intensive therapy, OS did not differ significantly (p = 0.394). With intensive therapy, significant differences in favor of de novo AML were observed in the ELN intermediate I/II (p = 0.009) and adverse (p = 0.016) risk groups but not within favorable risk groups (APL p = 0.927, ELN favorable p = 0.714). However, t-AML was no independent risk factor for OS (p = 0.103), RR (p = 0.982) and NRM (p = 0.320) in the multivariate analysis. A limitation of our study is an ELN 2010 risk stratification due to a lack of more comprehensive molecular data according to ELN 2022. We conclude that therapeutic algorithms in t-AML, in particular with regard to allo-HSCT, should be guided by ELN genetic risk rather than classification as t-AML alone. Our data support the WHO and ICC 2022 classifications, which include t-AML as diagnostic qualifier rather than a separate subcategory.

Regional disparities in the use of intensive chemotherapy for AML in the Netherlands: does it influence survival?

Objective

Acute myeloid leukaemia (AML) prognosis is enhanced with intensive remission induction chemotherapy (ICT) in eligible patients. However, ICT eligibility perceptions may differ among healthcare professionals. This nationwide, population-based study aimed to explore regional variation in ICT application and its relation with overall survival (OS).

Methods and analysis

We compared nine Dutch regional networks using data from the Netherlands Cancer Registry. Regional variance was assessed for the entire population and age subgroups (ie, ≤60 years and >60 years) using multivariable mixed effects logistic and Cox proportional hazard regression analyses, expressed via median OR (MOR) and median HR (MHR).

Results

Including all adult AML patients from 2014 to 2018 (N=4060 patients; 58% males; median age, 70 years), 1761 (43%) received ICT. ICT application varied from 36% to 57% (MOR 1.36 (95% CI 1.11 to 1.58)) across regions, with minor variations for patients aged ≤60 years (MOR 1.16 (95% CI 1.00 to 1.40)) and more extensive differences for those aged >60 years (MOR 1.43 (95% CI 1.16 to 1.63)). Median OS spanned 4.9-8.4 months across regions (MHR 1.11 (95% CI 1.00 to 1.15)), with pronounced differences in older patients (MHR 1.12 (95% CI 1.08 to 1.20)) but negligible differences in the younger group (MHR 1.02 (95% CI 1.00 to 1.14)). Survival differences for the total population and the older patients decreased to respectively, MHR 1.09 (95% CI 1.00 to 1.13) and 1.10 (95% CI 1.04 to 1.18), after additional adjustment for the probability of receiving ICT within a region, indicating approximately 10% unexplained differences.

Conclusion

Regional disparities in ICT application and survival exist, especially in older AML patients. However, ICT application differences partially explain survival disparities, indicating the need for more standardised ICT eligibility criteria and a better understanding of underlying causes of outcome disparities.

Advancements and Challenges in the Treatment of AML

The therapeutic arsenal for the management of AML has expanded significantly in recent years. Before 2017, newly diagnosed AML was treated with either standard cytarabine- and anthracycline-based induction chemotherapy (for all fit patients) or a single-agent hypomethylating agent (in unfit patients or those 75 years and older). While assessing patient fitness remains important, characterizing the disease biology has become critical to select the optimal initial therapy for each patient with more options available. FLT3 inhibitors, gemtuzumab ozogamicin, and CPX-351 have been shown to improve outcomes for specific subsets of patients. Venetoclax (VEN) with a hypomethylating agent (HMA) is the standard-of-care frontline regimen for most older patients, except perhaps for those with an IDH1 mutation where ivosidenib with azacitidine may also be considered. On the basis of the success seen with HMA/VEN in older patients, there is now increasing interest in incorporating VEN into frontline regimens in younger patients, with promising data from multiple early phase studies. This article focuses on recent updates and ongoing challenges in the management of AML, with a particular focus on the ongoing challenge of secondary AML and considerations regarding the selection of initial therapy in younger patients. An overview of common side effects and toxicities associated with targeted therapies is also presented here, along with recommended strategies to mitigate these risks.

[Efficacy and prognostic factors of allogeneic hematopoietic stem cell transplantation in the treatment of secondary acute myeloid leukemia]

Objective: To evaluate the efficacy and prognostic factors of allogeneic hematopoietic stem cell transplantation (allo-HSCT) in patients with secondary acute myeloid leukemia (sAML) . Methods: In this multicenter, retrospective clinical study, adult patients aged ≥18 years who underwent allo-HSCT for sAML at four centers of the Zhejiang Hematopoietic Stem Cell Transplantation Collaborative Group from January 2014 to November 2022 were included, and the efficacy and prognostic factors of allo-HSCT were analyzed. Results: A total of 95 patients were enrolled; 66 (69.5%) had myelodysplastic syndrome-acute myeloid leukemia (MDS-AML) , 4 (4.2%) had MDS/MPN-AML, and 25 (26.3%) had therapy-related AML (tAML) . The 3-year CIR, LFS, and overall survival (OS) rates were 18.6% (95% CI 10.2%-27.0%) , 70.6% (95% CI 60.8%-80.4%) , and 73.3% (95% CI 63.9%-82.7%) , respectively. The 3-year CIRs of the M-AML group (including MDS-AML and MDS/MPN-AML) and the tAML group were 20.0% and 16.4%, respectively (P=0.430) . The 3-year LFSs were 68.3% and 75.4%, respectively (P=0.176) . The 3-year OS rates were 69.7% and 75.4%, respectively (P=0.233) . The 3-year CIRs of the groups with and without TP53 mutations were 60.0% and 13.7%, respectively (P=0.003) ; the 3-year LFSs were 20.0% and 76.5%, respectively (P=0.002) ; and the 3-year OS rates were 40.0% and 77.6%, respectively (P=0.002) . According to European LeukmiaNet 2022 (ELN2022) risk stratification, the 3-year CIRs of patients in the low-, intermediate-, and high-risk groups were 8.3%, 17.8%, and 22.6%, respectively (P=0.639) . The three-year LFSs were 91.7%, 69.5%, and 65.6%, respectively (P=0.268) . The 3-year OS rates were 91.7%, 71.4%, and 70.1%, respectively (P=0.314) . Multivariate analysis revealed that advanced disease at allo-HSCT and TP53 mutations were independent risk factors for CIR, LFS, and OS. Conclusion: There was no significant difference in the prognosis of patients who underwent allo-HSCT among the MDS-AML, MDS/MPN-AML, and tAML groups. Advanced disease at transplantation and TP53 mutations were poor prognostic factors. ELN2022 risk stratification had limited value for predicting the prognosis of patients with sAML following allo-HSCT.

Salvage hematopoietic stem cell transplantation for patients with higher leukemia burden in relapsed or refractory acute myeloid leukemia: a ten-year study

Patients with relapsed and refractory acute myeloid leukemia (R-R AML), especially those in non-remission (NR) have a poor prognosis after allogeneic hematopoietic stem cell transplantation (allo-HSCT). In order to optimize the entire allo-HSCT process for R-R AML patients and identify potential factors affecting clinical outcomes after HSCT, we retrospectively analyzed 44 adult patients with R-R AML who underwent salvage allo-HSCT while in NR or with concomitant extramedullary leukemia at the Institute of Hematology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology from 2013 to 2022. The 1-year and 2-year overall survival (OS) of the 44 patients were 55.3% (95% confidence interval [CI], 41.1%-74.3%) and 44.4% (95%CI, 30.2%-65.4%), respectively. The 1-year and 2-year cumulative incidence of relapse (CIR) were 39.4% (95%CI, 38.0%-40.7%) and 53.0% (95%CI, 51.0%-55.1%), respectively, and the 1-year and 2-year leukemia-free survival (LFS) were 37.8% (95%CI, 24.8%-57.7%) and 20.3% (95%CI, 9.1%-45.3%), respectively. The 100-day, 1-year and 2-year treatment-related mortality (TRM) was 13.8% (95%CI, 13.3%-14.4%), 22.8% (95%CI, 21.9%-23.7%) and 26.7% (95%CI, 25.5%-27.8%), respectively. Multivariate analysis revealed that patients who developed chronic graft-versus-host disease (cGVHD) after transplantation had lower relapse rate. Our analysis also indicated that patients with blast counts in bone marrow (BM) <20% and those with ≥20% had comparable clinical outcomes after allo-HSCT. In conclusion, our study demonstrated that R-R AML patients in NR or with concomitant extramedullary leukemia can benefit from allo-HSCT, regardless of leukemia burden at the time of transplantation. Patients who experience cGVHD after allo-HSCT may have lower relapse rate due to enhanced graft-versus-leukemia (GVL) effects, but cGVHD should be controlled at mild to moderate level to avoid life-threatening complications.

NPM1-mutated acute myeloid leukemia: New pathogenetic and therapeutic insights and open questions

The nucleophosmin (NPM1) gene encodes for a multifunctional chaperone protein that is localized in the nucleolus but continuously shuttles between the nucleus and cytoplasm. NPM1 mutations occur in about one-third of AML, are AML-specific, usually involve exon 12 and are frequently associated with FLT3-ITD, DNMT3A, TET2, and IDH1/2 mutations. Because of its unique molecular and clinico-pathological features, NPM1-mutated AML is regarded as a distinct leukemia entity in both the International Consensus Classification (ICC) and the 5th edition of the World Health Organization (WHO) classification of myeloid neoplasms. All NPM1 mutations generate leukemic mutants that are aberrantly exported in the cytoplasm of the leukemic cells and are relevant to the pathogenesis of the disease. Here, we focus on recently identified functions of the NPM1 mutant at chromatin level and its relevance in driving HOX/MEIS gene expression. We also discuss yet controversial issues of the ICC/WHO classifications, including the biological and clinical significance of therapy-related NPM1-mutated AML and the relevance of blasts percentage in defining NPM1-mutated AML. Finally, we address the impact of new targeted therapies in NPM1-mutated AML with focus on CAR T cells directed against NPM1/HLA neoepitopes, as well as XPO1 and menin inhibitors.

Clinical outcome of therapy-related acute myeloid leukemia patients. Real-life experience in a University Hospital and a Cancer Center in France

BACKGROUND

t-AML occurs after a primary malignancy treatment and retains a poor prognosis.

AIMS

To determine the impact of primary malignancies, therapeutic strategies, and prognostic factors on clinical outcomes of t-AML.

RESULTS

A total of 112 adult patients were included in this study. Fifty-Five patients received intensive chemotherapy (IC), 33 non-IC, and 24 best supportive care. At t-AML diagnosis, 42% and 44% of patients presented an unfavorable karyotype and unfavorable 2010 ELN risk profile, respectively. Among treated patients (n = 88), 43 (49%) achieved complete remission: four out of 33 (12%) and 39 out of 55 (71%) in non-IC and IC groups, respectively. With a median follow-up of 5.5 months, the median overall survival (OS) and disease-free survival (DFS) for the whole population were 9 months and 6.3 months, respectively, and for the 88 treated patients 13.5 months and 8.2 months, respectively. Univariate analysis on OS and DFS showed a significant impact of high white blood cells (WBC) and blast counts at diagnosis, unfavorable karyotype and ELN classification. Multivariate analysis showed a negative impact of WBC count at diagnosis and a positive impact of chemotherapy on OS and DFS in the whole population. It also showed a negative impact of previous auto-HCT and high WBC count on OS and DFS and of IC on OS in treated patients which disappeared when we considered only confounding variables (age, previous cancers, marrow blasts, and 2010 ELN classification). In a pair-matched analysis comparing IC treated t-AML with de novo AML, there was no difference of OS and DFS between the two populations.

CONCLUSION

We showed, in this study that t-AML patients with unfavorable features represented almost half of the population. Best outcomes obtained in patients receiving IC must be balanced by known confounding variables and should be improved by using new innovative agents and therapeutic strategies.

Overlapping features of therapy-related and de novo NPM1-mutated AML

NPM 1-mutated acute myeloid leukemia (AML) shows unique features. However, the characteristics of "therapy-related" NPM1-mutated AML (t-NPM1 AML) are poorly understood. We compared the genetics, transcriptional profile, and clinical outcomes of t-NPM1 AML, de novo NPM1-mutated AML (dn-NPM1 AML), and therapy-related AML (t-AML) with wild-type NPM1 (t-AML). Normal karyotype was more frequent in t-NPM1 AML (n = 78/96, 88%) and dn-NPM1 (n = 1986/2394, 88%) than in t-AML (n = 103/390, 28%; P < .001). DNMT3A and TET2 were mutated in 43% and 40% of t-NPM1 AML (n = 107), similar to dn-NPM1 (n = 88, 48% and 30%; P > 0.1), but more frequently than t-AML (n = 162; 14% and 10%; P < 0.001). Often mutated in t-AML, TP53 and PPM1D were wild-type in 97% and 96% of t-NPM1 AML, respectively. t-NPM1 and dn-NPM1 AML were transcriptionally similar, (including HOX genes upregulation). At 62 months of median follow-up, the 3-year overall survival (OS) for t-NPM1 AML (n = 96), dn-NPM1 AML (n = 2394), and t-AML (n = 390) were 54%, 60%, and 31%, respectively. In multivariable analysis, OS was similar for the NPM1-mutated groups (hazard ratio [HR] 0.9; 95% confidence interval [CI], 0.65-1.25; P = .45), but better in t-NPM1 AML than in t-AML (HR, 1.86; 95% CI, 1.30-2.68; P < .001). Relapse-free survival was similar between t-NPM1 and dn-NPM1 AML (HR, 1.02; 95% CI, 0.72-1.467; P = .90), but significantly higher in t-NPM1 AML versus t-AML (HR, 1.77; 95% CI, 1.19-2.64; P = .0045). t-NPM1 and dn-NPM1 AML have overlapping features, suggesting that they should be classified as a single disease entity.

Association between Prior Cytotoxic Therapy, Antecedent Hematologic Disorder, and Outcome after Allogeneic Hematopoietic Cell Transplantation in Adult Acute Myeloid Leukemia

(1) Background: Secondary acute myeloid leukemia (AML), i.e., AML arising from prior therapy (therapy-related) and/or an antecedent hematologic disorder (AHD) is generally associated with worse outcomes compared to de novo AML. However, recognizing the prognostic importance of genetic characteristics rather than clinical history, secondary AML is now considered a diagnostic qualifier rather than a separate disease entity. (2) Methods: To assess the association between clinical history and AML outcomes in the context of allogeneic hematopoietic cell transplantation (HCT), we retrospectively analyzed 759 patients with de novo AML, 115 with AHD AML, and 105 with therapy-related AML who received first allografts while in first or second remission. (3) Results: At the time of HCT, these three cohorts differed significantly regarding many patient and disease-specific characteristics, including age (p < 0.001), gender (p < 0.001), disease risk (p = 0.005), HCT-CI score (p < 0.001), blood count recovery (p = 0.003), first vs. second remission (p < 0.001), remission duration (p < 0.001), measurable residual disease (MRD; p < 0.001), and conditioning intensity (p < 0.001). Relative to patients with de novo AML, relapse rates were similar for patients with AHD (hazard ratio [HR] = 1.07, p = 0.7) and therapy-related AML (HR = 0.86, p = 0.4) after multivariable adjustment, as were relapse-free survival (HR = 1.20, p = 0.2, and HR = 0.89, p = 0.5) and overall survival (HR = 1.19, p = 0.2, and HR = 0.93, p = 0.6). Non-relapse mortality was higher for AHD AML (HR = 1.59, p = 0.047). (4) Conclusions: These data suggest that the clinical history by itself contains limited prognostic value for adults with AML undergoing allografting, supporting the most recent approach to use this information as a diagnostic qualifier rather than a disease entity.

Clinicopathologic and Molecular Analysis of Normal Karyotype Therapy-Related and De Novo Acute Myeloid Leukemia: A Multi-Institutional Study by the Bone Marrow Pathology Group

PURPOSE

Therapy-related acute myeloid leukemias (t-AML) are a heterogenous group of aggressive neoplasms that arise following exposure to cytotoxic chemotherapy and/or ionizing radiation. Many therapy-related myeloid neoplasms (t-MN) are associated with distinct chromosomal aberrations and/or TP53 alterations, but little is known about the clinicopathologic and molecular features of normal karyotype t-AML (NK-t-AML) and whether this t-MN subtype is distinctly different from NK de novo AML (NK-dn-AML).

METHODS

This multi-institutional study by the Bone Marrow Pathology Group retrospectively evaluated clinicopathologic and molecular characteristics of 335 patients with NK-AML, comprising 105 t-AML and 230 dn-AML cases.

RESULTS

Patients with t-AML compared with dn-AML exhibit significantly shorter overall survival (OS; median months: 17.6 v 44.2; P < .0001) and relapse-free survival (RFS; median months: 9.1 v 19.2; P = .0018). Frequency of NPM1, FLT3, KRAS, and GATA2 mutations were significantly different in NK-t-AML compared with NK-dn-AML (NPM1 35% v 49%; P = .0493; FLT3 23% v 36%; P = 0494; KRAS 12% v 5%; P = .0465; GATA2 9% v 2% P = .0105), while TP53 mutations were rare. Patients with t-AML more often stratified into intermediate or adverse 2017 ELN genetic risk groups. Favorable ELN risk predicted favorable OS (hazard ratio [HR], 0.4056; 95% CI, 0 to 0.866; P = .020) and RFS (HR, 0.355; 95% CI, 0 to 0.746; P = .006). Among all patients with NK-AML, stem-cell transplant and favorable ELN risk both significantly affected RFS, while therapy-relatedness and age had a borderline significant impact on OS (HR, 1.355; 95% CI, 0.975 to 1.882; P = .070).

CONCLUSION

To our knowledge, this is the largest study to date to comprehensively evaluate NK-t-AML and provides a framework that may inform our understanding of NK-t-AML disease biology and could potentially help guide therapeutic management and improved disease classification in t-MNs that lack cytogenetic aberrations.

Allogeneic Hematopoietic Stem Cell Transplantation for Relapsed/Refractory Acute Myeloid Leukemia: A Single-Centre Experience

INTRODUCTION

Patients with relapsed/refractory acute myeloid leukemia (r/r AML) are characterized as having a poor prognosis. The only viable option of treatment for these patients is allogenic stem cell transplantation (allo-HSCT). Therefore, we have attempted to analyse factors related to both the disease itself and the transplantation procedure that could have an influence on the improvement of outcomes in this group of patients.

PATIENTS AND METHODS

Sixty-four patients with r/r AML underwent allo-HSCT at our center in 2012 to 2021. Fifty-two had active disease at the beginning of theallo-HSCT procedure, with amedian number of blasts in bone marrow (BM) of 18, and 12 had therapeutic aplasia after the last reinduction (blasts < 5% in BM).

RESULTS

The probability of overall survival (OS) at 2 years was 25%. The median follow-up for survivors was 21.5 months. Progression-free survival (PFS) estimates were above 46%. The main cause of death was disease progression (49%). A statistically significant effect on premature death was reported for the diagnosis of secondary AML (sAML) and cytomelovirus (CMV) reactivation post allo-HSCT. On the other hand, chronic graft versus host disease (cGVHD) decreased the risk of disease progression. sAML and CMV reactivation were found to have opposite effects.

Prognostic impact of the AML ELN2022 risk classification in patients undergoing allogeneic stem cell transplantation

For most patients with acute myeloid leukemia (AML), an allogeneic hematopoietic stem cell transplantation (HSCT) offers the highest chance of cure. Recently, the European LeukemiaNet (ELN) published updated recommendations on the diagnosis and risk classification in AML based on genetic factors at diagnosis as well as a dynamic adjustment (reclassification) according to the measurable residual disease (MRD) status for the favorable and intermediate risk groups. Validation of the ELN2022 risk classification has not been reported. We retrospectively analyzed 522 AML patients who received an HSCT at a median age of 59 (range 16-76) years. For patients with adequate material available and in remission prior to HSCT (n = 229), the MRD status was evaluated. Median follow-up after HSCT was 3.0 years. ELN2022 risk at diagnosis was in 22% favorable, in 26% intermediate, and in 52% adverse. ELN2022 risk at diagnosis is associated with the cumulative incidence of relapse/progression (CIR), event-free survival (EFS), and overall survival (OS) in the whole patient cohort, as well as the subgroup of patients transplanted in first remission. However, the risk stratification based on the ELN2022 classification did not significantly improve outcome prognostication in comparison to the ELN2017 classification. In our study, the newly added group of patients with myelodysplasia-related gene mutations did not have adverse outcomes. Re-classifying these patients into the intermediate risk group and adjusting the grouping for all AML patients by MRD at HSCT, led to a refined and improved risk stratification, which should be validated in independent studies.

Diagnosis and management of AML in adults: 2022 recommendations from an international expert panel on behalf of the ELN

The 2010 and 2017 editions of the European LeukemiaNet (ELN) recommendations for diagnosis and management of acute myeloid leukemia (AML) in adults are widely recognized among physicians and investigators. There have been major advances in our understanding of AML, including new knowledge about the molecular pathogenesis of AML, leading to an update of the disease classification, technological progress in genomic diagnostics and assessment of measurable residual disease, and the successful development of new therapeutic agents, such as FLT3, IDH1, IDH2, and BCL2 inhibitors. These advances have prompted this update that includes a revised ELN genetic risk classification, revised response criteria, and treatment recommendations.

A Synopsis Clonal Hematopoiesis of Indeterminate Potential in Hematology

Simple Summary

Mutations are not the norm, yet they exist. Having some mutations can infer information about a precancerous state. Clonal hematopoiesis of indeterminate potential is a condition of recurrent somatic mutations in the blood of otherwise healthy adults. In this review, we unravel the role of these mutations in multiple myeloma.

Abstract

Clonal hematopoiesis of indeterminate potential can be defined as genetic mutations that correlate in hematologic neoplasia such as myelodysplastic syndrome. Patients with cytopenia increasingly undergo molecular genetic tests of peripheral blood or bone marrow for diagnostic purposes. Recently, a new entity has been demarcated to lessen the risk of incorrect diagnoses of hematologic malignancies. This new entity is a potential precursor of myeloid diseases, analogous to monoclonal gammopathy of undetermined significance as a potential precursor of multiple myeloma.

Allogeneic hematopoietic cell transplantation in patients with therapy-related myeloid neoplasm after breast cancer: a study of the Chronic Malignancies Working Party of the EBMT

We performed a registry study on therapy-related myeloid neoplasm (t-MN), both therapy-related myelodysplastic syndrome (t-MDS) and acute myeloid leukemia (t-AML) following treatment for breast cancer who underwent a first allogeneic hematopoietic cell transplant (allo-HCT). Of 252 identified female patients (median age 57 years), 77% were transplanted for t-AML and 23% for t-MDS, with a median time from breast cancer diagnosis to the diagnosis of tMN and subsequent allo-HCT of 3.7 and 4.6 years, respectively. At transplant, 191 patients were in remission for breast cancer, while 4 were not (57 missing). T-MN was in a complete remission at the time of transplant in 67% of patients. 2-year overall survival, relapse free-survival, relapse incidence and non-relapse mortality were 50%, 45%, 33%, and 22%, respectively. Multivariable analysis revealed that if the t-MN was not in CR pre-transplant, this was associated with lower OS, RFS, and a higher relapse incidence. Seventeen cases of breast cancer recurrence were recorded after a median of 2.4 years post-transplant, and relapse of primary breast cancer accounted for 7% of deaths. This study indicates that allo-HCT for t-MN following treatment for breast cancer shows encouraging transplant outcomes. The incidence of breast cancer relapse post-transplant remains a cause for concern.

Secondary Acute Myeloid Leukemia (sAML): Similarly Dismal Outcomes of AML After an Antecedent Hematologic Disorder and Therapy Related AML

Therapy related acute myeloid leukemia (tAML) and secondary AML after an antecedent hematologic disorder (sAML-AHD) are often addressed together, blurring any clinical and prognostic differences. Among 516 AML patients, we compared characteristics and outcomes of 149 patients with "sAML" (sAML-AHD: 104, tAML: 45), uniformly and intensively treated during the last 2 decades at 1 center. Clinical outcomes of the whole "sAML" cohort were significantly inferior compared to de novo AML and in both intermediate and poor cytogenetic risk groups. Adverse karyotype had no effect on survival in tAML, while it was a negative predictor in sAML-AHD. Both groups showed similarly dismal outcome, with low complete remission rates (CR 44% vs. 41%) and median overall survival (OS 7 vs. 10.5 months). Allogeneic hematopoietic cell transplantation (alloHCT) recipients in CR1 had superior median OS (24 vs. 8 months). By multivariate analysis, alloHCT was an independent predictor of outcome, while karyotype was for sAML-AHD only. In conclusion, both "sAML" groups have inferior outcomes after chemotherapy, with adverse karyotype affecting primarily sAML-AHD. Until new treatment approaches are available, only alloHCT offers a survival advantage.

Clinical implications of SRSF2 mutations in AML patients undergoing allogeneic stem cell transplantation

The SRSF2 mutations are frequently found in acute myeloid leukemia (AML) and mostly affect the P95 residue. Mutations in this splicing factor mediate abnormal splicing associated with exon skipping events, including EZH2 as a crucial target. While SRSF2 mutations are enriched in secondary AML and associated with worse outcomes following chemotherapy consolidation, very little is known about the associated biological and clinical implications in AML patients consolidated with allogeneic hematopoietic stemcell transplantation (HSCT). Here we retrospectively analyzed 263 adult AML patients who received an allogeneic HSCT regarding the biological and clinical implications of the SRSF2 mutation status at diagnosis and in morphologic remission at HSCT. We found 12.5% of the patients to be SRSF2 mutated at diagnosis. Mutated patients had increased EZH2 missplicing events with P95H likely driving this pathobiology most effectively. However, the amount of EZH2 missplicing events, as a functional surrogate marker did not associate with relevant biological or clinical characteristics. We observed a persistence of mutations in remission before HSCT in the majority (93%) of SRSF2 mutated AML patients. Importantly, the variant allele frequency (VAF) levels of SRSF2 mutations in remission at HSCT did not correlate with outcomes following HSCT consolidation, limiting the applicability of SRSF2 mutations as a marker for residual AML disease. Following allogeneic HSCT SRSF2 mutated AML patients experienced a 2-year overall survival of 77%, indicating that SRSF2 mutated AML patients may benefit from HSCT consolidation.

Impact of induction chemotherapy with intermediate-dosed cytarabine and subsequent allogeneic stem cell transplantation on the outcome of high-risk acute myeloid leukemia

Background

Acute myeloid leukemia (AML) with antecedent hematological disease (s-AML) and treatment-related AML (t-AML) predicts poor prognosis. Intensive treatment protocols of those high-risk patients should consider allogeneic stem cell transplantation (allo-HSCT) in first complete remission (CR). Despite allo-HSCT, relapse rate remains high. Induction chemotherapy with liposomal cytarabine and daunorubicin (CPX-351) has been approved for patients with AML with myeloid-related changes (AML-MRC) or t-AML based on improved survival and remission rates compared to standard 7 + 3 induction.

Patients and methods

110 patients with newly diagnosed s-AML or t-AML at a university hospital were analyzed retrospectively. Median age was 62 years (24–77 years). A total of 65 patients with s-AML after MDS (59%) and 23 patients (20.9%) with t-AML were included. Induction chemotherapy consisted of intermediate-dosed cytarabine (ID-AraC) in combination with idarubicin (patients up to 60 years) or mitoxantrone (patients over 60 years). In patients subsequently undergoing allo-HSCT, reduced conditioning regimens (RIC) were applied prior to transplantation in 47 of 62 patients (76%).

Results

Induction chemotherapy with ID-AraC resulted in an overall response rate of 83% including complete remission (CR/CRi) in 69 patients (63%) with a low rate of early death (2.7%). Most relevant non-hematologic toxicity consisted of infectious complications including sepsis with need of intensive care treatment in five patients (4.5%) and proven or probable invasive fungal disease in eight patients (7.2%). Relapse-free survival (RFS), event-free survival (EFS) and overall survival (OS) of the whole cohort were 19 months (0–167), 10 months (0–234) and 15 months (0–234), respectively (p < 0.0001). A significant improvement of OS was observed in patients who underwent allo-HSCT compared to those without subsequent allo-HSCT: 9 vs. 46 months, p < 0.0001. Rate of transplantation-related mortality (TRM) in the early phase post allo-HSCT was low (0.9% at day 30 and 1.8% at day 90, respectively). RIC conditioning results in OS rate of 60% after 60 months post allo-HSCT (median OS not reached).

Conclusion

S-AML and t-AML patients receiving induction chemotherapy with intermediate-dosed cytarabine showed satisfactory response rate and consolidation therapy with allo-HSCT after full or reduced-intensity conditioning further improved survival in these patients with similar outcome as reported for CPX-351.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00432-021-03733-0.

What's new in the pathogenesis and treatment of therapy-related myeloid neoplasms

Therapy-related myeloid neoplasms (t-MN) include diseases onsetting in patients treated with chemo- and/or radiotherapy for a primary cancer, or an autoimmune disorder. Genomic variants, in particular in familial cancer genes, may play a predisposing role. Recent advances in deep sequencing techniques have shed light on the pathogenesis of t-MN, identifying clonal hematopoiesis of indeterminate potential (CHIP) as a frequent first step in the multi-hit model of t-MN. CHIP is often detectable prior to any cytotoxic treatment, probably setting the fertile genomic background for secondary leukemogenesis. The evolution pattern towards t-MN is then a complex process, shaped by the type of cancer therapy, the aging process, and the individual exposures, that favor additional hits, such as the acquisition of TP53 mutations and unfavorable karyotype abnormalities. The pathogenesis of t-MN differs from MN associated with environmental exposure. Indeed, the genetic aberration patterns of MN developing in atomic bomb survivors show few mutations in classical DNA methylation genes, and a high prevalence of 11q and ATM alterations, together with TP53 mutations. Survival in t-MN is poor. In addition to the biology of t-MN, the patient's previous disease history and the remission status at t-MN diagnosis are significant factors contributing to unfavorable outcome. New drugs active in secondary leukemias include CPX-351, or venetoclax in combination with hypomethylating agents, monoclonal antibodies as magrolimab, or targeted drugs against pathogenic mutations. Allogeneic stem cell transplantation remains the best currently available therapeutic option with curative intent for fit patients with unfavorable genetic profiles.