Treatment benefit of upfront autologous stem cell transplantation for newly diagnosed multiple myeloma: a systematic review and meta-analysis.

BACKGROUND: Upfront high-dose therapy (HDT) followed by autologous stem cell transplantation (ASCT) remains a profitable strategy for newly diagnosed multiple myeloma (MM) patients in the context of novel agents. However, current knowledge demonstrates a discrepancy between progression-free survival (PFS) and overall survival (OS) benefit with HDT/ASCT. METHODS: We conducted a systematic review and meta-analysis that included both randomized controlled trials (RCTs) and observational studies evaluating the benefit of upfront HDT/ASCT published during 2012 to 2023. Further sensitivity analysis and meta-regression were also performed. RESULTS: Among the 22 enrolled studies, 7 RCTs and 9 observational studies had a low or moderate risk of bias, while the remaining 6 observational studies had a serious risk of bias. HDT/ASCT revealed advantages in complete response (CR) with an odds ratio (OR) of 1.24 and 95% confidence interval (CI) 1.02 ~ 1.51, PFS with a hazard ratio (HR) of 0.53 (95% CI 0.46 ~ 0.62), and OS with an HR of 0.58 (95% CI 0.50 ~ 0.69). Sensitivity analysis excluding the studies with serious risk of bias and trim-and-fill imputation fundamentally confirmed these findings. Older age, increased percentage of patients with International Staging System (ISS) stage III or high-risk genetic features, decreased proteasome inhibitor (PI) or combined PI/ immunomodulatory drugs (IMiD) utilization, and decreased follow-up duration or percentage of males were significantly related to a greater survival advantage with HDT/ASCT. CONCLUSIONS: Upfront ASCT remains a beneficial treatment for newly diagnosed MM patients in the period of novel agents. Its advantage is especially acute in high-risk MM populations, such as elderly individuals, males, those with ISS stage III or high-risk genetic features, but is attenuated with PI or combined PI/IMiD utilization, contributing to divergent survival outcomes.

Distinct genetic landscapes and their clinical implications in younger and older patients with myelodysplastic syndromes.

Myelodysplastic syndromes (MDS) are a group of clinically and genetically diverse diseases that impose patients with an increased risk of leukemic transformation. While MDS is a disease of the elderly, the interplay between aging and molecular profiles is not fully understood, especially in the Asian population. Thus, we compared the genetic landscape between younger and older patients in a cohort of 698 patients with primary MDS to advance our understanding of the distinct pathogenesis and different survival impacts of gene mutations in MDS according to age. We found that the average mutation number was higher in the older patients than younger ones. The younger patients had more WT1 and CBL mutations, but less mutated ASXL1, DNMT3A, TET2, SF3B1, SRSF2, STAG2, and TP53 than the older patients. In multivariable survival analysis, RUNX1 mutations with higher variant allele frequency (VAF) and U2AF1 and TP53 mutations were independent poor prognostic indicators in the younger patients, whereas DNMT3A and IDH2 mutations with higher VAF and TP53 mutations conferred inferior outcomes in the older patients. In conclusion, we demonstrated the distinct genetic landscape between younger and older patients with MDS and suggested that mutations impact survival in an age-depended manner.

Epigenetic remodeling of the immune landscape in cancer: therapeutic hurdles and opportunities.

The tumor immune microenvironment represents a sophisticated ecosystem where various immune cell subtypes communicate with cancer cells and stromal cells. The dynamic cellular composition and functional characteristics of the immune landscape along the trajectory of cancer development greatly impact the therapeutic efficacy and clinical outcome in patients receiving systemic antitumor therapy. Mounting evidence has suggested that epigenetic mechanisms are the underpinning of many aspects of antitumor immunity and facilitate immune state transitions during differentiation, activation, inhibition, or dysfunction. Thus, targeting epigenetic modifiers to remodel the immune microenvironment holds great potential as an integral part of anticancer regimens. In this review, we summarize the epigenetic profiles and key epigenetic modifiers in individual immune cell types that define the functional coordinates of tumor permissive and non-permissive immune landscapes. We discuss the immunomodulatory roles of current and prospective epigenetic therapeutic agents, which may open new opportunities in enhancing cancer immunotherapy or overcoming existing therapeutic challenges in the management of cancer.

Clinico-genetic and prognostic analyses of 716 patients with primary myelodysplastic syndrome and myelodysplastic syndrome/acute myeloid leukemia based on the 2022 International Consensus Classification.

The 2022 International Consensus Classification (ICC) recategorized myeloid neoplasms based on recent advances in the understanding of the biology of hematologic malignancies, in which myelodysplastic syndrome (MDS) with blasts of 10%-19% is classified as MDS/acute myeloid leukemia (AML), MDS with mutated SF3B1, irrespective of the number of ring sideroblasts, as MDS-SF3B1, and those with multi-hit TP53 mutations as MDS with mutated TP53. In the analysis of 716 patients with MDS diagnosed according to the 2016 WHO classification, we found that 75.3% of patients remained in the MDS group based on the ICC, while 24.7% of patients were reclassified to the MDS/AML group after the exclusion of 15 patients who were classified to the AML group. Patients with MDS/AML showed a distinct mutational landscape and had poorer outcomes, compared to those with MDS. In the MDS group, patients with MDS-SF3B1 had higher frequencies of DNMT3A and TET2 mutations than those with MDS, not otherwise specified, with single lineage dysplasia or multilineage dysplasia. Patients with mutated TP53 were associated with dismal outcomes, irrespective of the blast percentage. In conclusion, this study showed that the ICC facilitates efficient segregation and risk-stratification of MDS which can help guide the treatment choice of patients with the disease.

Validation of the prognostic significance of the 2022 European LeukemiaNet risk stratification system in intensive chemotherapy treated aged 18 to 65 years patients with de novo acute myeloid leukemia.

The European LeukemiaNet (ELN) recently proposed a revised recommendation for the diagnosis and management of acute myeloid leukemia (AML) in adults, recognized as ELN-2022. However, validation in a large real-world cohort remains lacking. In this study, we aimed to validate the prognostic relevance of the ELN-2022 in a cohort of 809 de novo, non-M3, younger (ages 18-65 years) AML patients receiving standard chemotherapy. The risk categories of 106 (13.1%) patients were reclassified from that determined using ELN-2017 to that determined using ELN-2022. The ELN-2022 effectively helped distinguish patients as favorable, intermediate, and adverse risk groups in terms of remission rates and survival. Among patients who achieved first complete remission (CR1), allogeneic transplantation was beneficial for those in the intermediate risk group, but not for those in the favorable or adverse risk groups. We further refined the ELN-2022 system by re-categorizing AML patients with t(8;21)(q22;q22.1)/RUNX1::RUNX1T1 with KIThigh , JAK2 or FLT3-ITDhigh mutations into the intermediate risk subset, AML patients with t(7;11)(p15;p15)/NUP98::HOXA9 and AML patients with co-mutated DNMT3A and FLT3-ITD into the adverse risk subsets, and AML patients with complex or monosomal karyotypes, inv (3)(q21.3q26.2) or t(3;3)(q21.3;q26.2)/GATA2,MECOM(EVI1) or TP53 mutation into the very adverse risk subset. The refined ELN-2022 system performed effectively to distinguish patients as favorable, intermediate, adverse, and very adverse risk groups. In conclusion, the ELN-2022 helped distinguish younger, intensively treated patients into three groups with distinct outcomes; the proposed refinement of ELN-2022 may further improve risk stratification among AML patients. Prospective validation of the new predictive model is necessary.

Polatuzumab vedotin-based salvage immunochemotherapy as third-line or beyond treatment for patients with diffuse large B-cell lymphoma: a real-world experience.

Polatuzumab vedotin (PoV) has recently shown promising activity when combined with rituximab-bendamustine (BR) in patients with relapsed/refractory (R/R) diffuse large B-cell lymphoma (DLBCL). However, few studies have described the prognostic factors predicting response. Here, we aimed to evaluate the efficacy and safety profile of PoV-based chemotherapy, including regimens other than BR, as third-line or beyond treatment for patients with R/R DLBCL and to explore prognostic factors. Overall, 40 patients, including 37 with de novo and 3 with transformed DLBCL, were enrolled. The overall response rate was 52.5%, and 25% and 27.5% of patients showed a complete response and partial response, respectively. With a median follow-up of 18.8 months, the median overall survival (OS) of the total cohort was 8.5 months, and that of those receiving subsequent hematopoietic stem cell transplantation (HSCT) was 24 months. Low/intermediate risk according to the revised International Prognostic Index score at diagnosis and before PoV treatment predicted better OS. Furthermore, a normal lactate dehydrogenase level and an absolute lymphocyte count/absolute monocyte count ratio > 1.5 were favorable OS prognostic factors. The most common adverse event was cytopenia, with 42.5% of patients developing febrile neutropenia. Grade 1-3 peripheral neuropathy associated with PoV was reported in 25% of patients and resolved in most patients after the cessation of treatment. In summary, we demonstrated that PoV combined with either BR or other intensive chemotherapy is an effective and well-tolerated salvage option for patients with R/R DLBCL. Subsequent HSCT has the potential to further improve survival outcomes in this high-risk population. Clinicaltrials.gov number: NCT05006534.

Cytogenetics and mutations could predict outcome in relapsed and refractory acute myeloid leukemia patients receiving BCL-2 inhibitor venetoclax.

Venetoclax, a selective B cell leukemia/lymphoma-2 (BCL2) inhibitor, has recently shown activity in relapsed or refractory (R/R) acute myeloid leukemia (AML). Effective biomarkers for identifying patients most likely to respond to venetoclax-based treatment are of clinical utility. In this study, we aimed to evaluate the efficacy and safety profiles of venetoclax-based therapy in a total 40 R/R AML patients and identify the potentially predictive factors for response. Overall response rate was 50%, including 9 (22.5%) complete response (CR) or CR with incomplete hematologic recovery of either neutrophil or platelet counts (CRi). Median time to best response was 1.4 months and the median overall survival (OS) was 6.6 months. Presence of intermediate-risk cytogenetics predicted better OS compared to unfavorable-risk cytogenetics. Patients harboring NPM1, RUNX1, or SRSF2 mutations seemed to have higher CR/CRi rates and median OS was significantly longer in RUNX1-mutated patients. On the contrary, patients with FLT3-ITD, TP53, or DNMT3A mutations did not reach any objective response and had worse OS. No laboratory or clinical tumor lysis syndrome was observed and the most common adverse events were prolonged cytopenias which resulted in 67.5% of febrile neutropenia. Patients with concurrent use of azole antifungals had similar incidence of cytopenias compared with those without azole antifungals. In summary, we demonstrate that venetoclax is an effective and well-tolerated salvage option for R/R AML patients. Survival benefits were particularly remarkable in patients with intermediate-risk cytogenetics or RUNX1 mutations. In contrast, TP53, NRAS, and DNMT3A mutations as well as FLT3-ITD conferred negative impact on survival.

Chronic disseminated candidiasis manifesting as hepatosplenic abscesses among patients with hematological malignancies.

BACKGROUND: The outcomes of deep-seated abscesses attributed to chronic disseminated candidiasis (CDC) in patients with hematological malignancies have rarely been reported in recent years. METHODS: We retrospectively reviewed and analyzed the data of patients with hematological malignancies who received a diagnosis of CDC at a medical center in Taiwan between 2008 and 2013. RESULTS: Sixty-one patients (32 men and 29 women) were diagnosed with CDC. The median age was 51 years (range: 18-83). The overall incidence of CDC was 1.53 per 100 patient-years in patients with hematological malignancies between 2008 and 2013. The highest incidence of CDC was 4.3 per 100 patient-years for acute lymphoblastic leukemia, followed by 3.6 for acute myeloid leukemia. We detected 3 (4.9%) proven, 13 (21.3%) probable, and 45 (73.8%) possible cases of CDC. A total of 13 patients had positive blood cultures for Candida species: C. tropicalis (8), C. albicans (2), C. glabrata (2), and C. famata (1). The median duration of antifungal treatment was 96 days (range: 7-796 days). Serial imaging studies revealed that the resolution rate of CDC was 30.0% at 3 months and 54.3% at 6 months. Five patients (8.2%) had residual lesions that persisted beyond one year. A multivariate analysis of the 90-day outcome revealed that shock was the only independent prognostic factor of 90-day survival in patients with CDC. CONCLUSION: The incidence of CDC did not decrease between 2008 and 2013. Patients with acute leukemia had a higher risk of CDC than those with other hematological malignancies. Imaging studies conducted at 6 months after diagnosis revealed that only half of the patients showed complete resolution. CDC requires prolonged treatment, and serial imaging at 6 months interval is suggested. Shock is the only independent prognostic factor of 90-day survival in patients with CDC.

Brentuximab vedotin as a salvage treatment for relapsed and refractory Hodgkin lymphoma patients in Taiwan.

Hodgkin lymphoma (HL) is a highly curable hematologic malignancy. Relapsed/refractory (R/R) HL is an important clinical challenge, despite advances in treatment. Brentuximab vedotin (BV) is highly effective in R/R HL in the western world. However, there are no real-world data on the use of BV in the Asian population. Our study aimed to evaluate the efficacy and safety of BV as salvage therapy in R/R HL patients in Taiwan. We recruited 20 R/R HL patients who received BV at National Taiwan University Hospital. BV was administered at 1.8 mg/kg once every 3 weeks. The median number of systemic treatment received before BV was three. The overall response rate was 73.7% with a complete remission rate of 21.1% in R/R HL. Overall survival was not reached and progression-free survival was 6.8 months. BV could strengthen disease control before transplantation and improve post-transplant outcomes, even among those heavily pretreated patients, without significant overlapping toxicities with prior therapies. Our data suggest that BV is well tolerated and effective in the treatment of Asian patients with R/R HL. BV may offer long-term disease control in selected patients.

Hyperleukocytosis is associated with distinct genetic alterations and is an independent poor-risk factor in de novo acute myeloid leukemia patients.

OBJECTIVES: Acute myeloid leukemia (AML) with hyperleukocytosis (HL) is intuitively thought as a unique group with dismal prognosis. However, comprehensive studies regarding the genetic landscape and clinical outcome in this group of patients are limited. METHODS: A total of 693 newly diagnosed de novo non-M3 AML patients were consecutively enrolled. We compared relevant mutations in 20 genes between AML patients with or without HL and exposed their prognostic implications. RESULTS: Hyperleukocytosis, defined as initial white blood cell counts above 50 000/µL, occurred in 28.9% of AML patients. HL patients had higher incidences of FLT3-ITD, NPM1, DNMT3A, CEBPA, and TET2 mutations. Multivariate analysis demonstrated that HL was an independent poor prognostic factor for overall survival and disease-free survival in total patients, those with intermediate-risk cytogenetics and normal karyotype irrespective of genetic alterations. Intriguingly, HL predicted poor survival in CEBPA double mutated, NPM1 + /FLT3-ITD- and NPM1-/FLT3-ITD- patients. Further, HL patients who received allogeneic hematopoietic stem cell transplantation (allo-HSCT) in first complete remission (CR) had a significantly longer overall survival and disease-free survival than those without allo-HSCT. CONCLUSIONS: Hyperleukocytosis is an independent poor prognostic factor irrespective of cytogenetics and mutation status. Allo-HSCT in first CR seems to ameliorate the poor prognostic impact of HL.

Hepatitis B reactivation among 1962 patients with hematological malignancy in Taiwan.

BACKGROUND: The risk of Hepatitis B virus (HBV) reactivation in patients with different hematological malignancy except lymphoma were rarely known before. METHODS: A total of 1962 patients with hematological malignancy were enrolled and followed-up at the National Taiwan University Hospital between 2008 and 2013. The clinical characteristics, HBV serology, and laboratory data were retrospectively reviewed and analyzed. RESULTS: A total of 1962 patients comprising 1048 men and 914 women were studied. The median age of the patients was 55 years (range, 15-97 years). Chronic HBV carriage was documented at diagnosis of hematological malignancy in 286 (14.6%) patients. A total of 171 (59.8%) of the 286 HBV carriers received primary prophylaxis with anti-HBV agents. Of the HBV carriers, 97 (33.9%) developed hepatitis B reactivation during or after chemotherapy, including 59 patients who had discontinued antiviral therapy. The incidence of hepatitis B reactivation among patients with hematological malignancy and HBV carriage was 10.4 per 100 person-years. A multivariate analysis revealed hepatocellular carcinoma (p < 0.001) and antiviral prophylaxis use (p < 0.001) were independent risk factors of HBV reactivation in HBV carriers. Of the 1676 patients with initial negative hepatitis B surface antigen (HBsAg) counts, 41 (2.4%) experienced hepatitis B reactivation, reverse seroconversion of HBsAg, and lost their protective hepatitis B surface antibody (anti-HBs). A multivariate analysis revealed that diabetes mellitus (p = 0.005, odds ratio (OR): 0.218, 95% confidence interval (CI): 0.076-0.629), allogeneic transplantation (p = 0.013, OR: 0.182, 95% CI: 0.047-0.701), liver cirrhosis (p < 0.001, OR: 0.002, 95% CI: 0-0.047), low anti-HBs titers (p = 0.016, OR: 0.020, 95% CI: 0.001-0.480), and positive hepatitis B core antibody (p = 0.013, OR: 0.070, 95% CI: 0.009-0.571) were independent risk factors of positive seroconversion of HBsAg in patients with hematological malignancy. CONCLUSIONS: The incidence of HBV reactivation among the patients with varying subtypes of hematological malignancy is similar. Prophylaxis with anti-HBV agents critically reduced the risk of hepatitis B reactivation.

CEBPA mutations in acute myeloid leukemia: implications in risk stratification and treatment.

Mutations in CCAAT enhancer binding protein α (CEBPA) occur in approximately 10% of patients with de novo acute myeloid leukemia (AML). Emerging evidence supports that in-frame mutations in the basic leucine zipper domain of CEBPA (CEBPAbZIP-inf) confer a survival benefit, and CEBPAbZIP-inf replaced CEBPA double mutations (CEBPAdm) as a unique entity in the 2022 World Health Organization (WHO-2022) classification and International Consensus Classification (ICC). However, challenges remain in daily clinical practice since more than 30% patients with CEBPAbZIP-inf die of AML despite intensive treatment. This review aims to provide a comprehensive summary of the heterogeneities observed in AML with CEBPAdm and CEBPAbZIP-inf, and will discuss the prognostic implications of concurrent mutations and novel mechanistic targets that may inform future drug development. The ultimate goal is to optimize clinical management and to provide precision medicine for this category of patients.

Comparison of the 2022 world health organization classification and international consensus classification in myelodysplastic syndromes/neoplasms.

In 2022, two novel classification systems for myelodysplastic syndromes/neoplasms (MDS) have been proposed: the International Consensus Classification (ICC) and the 2022 World Health Organization (WHO-2022) classification. These two contemporary systems exhibit numerous shared features but also diverge significantly in terminology and the definition of new entities. Thus, we retrospectively validated the ICC and WHO-2022 classification and found that both systems promoted efficient segregation of this heterogeneous disease. After examining the distinction between the two systems, we showed that a peripheral blood blast percentage ≥ 5% indicates adverse survival. Identifying MDS/acute myeloid leukemia with MDS-related gene mutations or cytogenetic abnormalities helps differentiate survival outcomes. In MDS, not otherwise specified patients, those diagnosed with hypoplastic MDS and single lineage dysplasia displayed a trend of superior survival compared to other low-risk MDS patients. Furthermore, the impact of bone marrow fibrosis on survival was less pronounced within the ICC framework. Allogeneic transplantation appears to improve outcomes for patients diagnosed with MDS with excess blasts in the ICC. Therefore, we proposed an integrated system that may lead to the accurate diagnosis and advancement of future research for MDS. Prospective studies are warranted to validate this refined classification.

Dysregulated immune and metabolic pathways are associated with poor survival in adult acute myeloid leukemia with CEBPA bZIP in-frame mutations.

Acute myeloid leukemia (AML) with CEBPA bZIP in-frame mutations (CEBPAbZIP-inf) is classified within the favorable-risk group by the 2022 European LeukemiaNet (ELN-2022). However, heterogeneous clinical outcomes are still observed in these patients. In this study, we aimed to investigate the mutation profiles and transcriptomic patterns associated with poor outcomes in patients with CEBPAbZIP-inf. One hundred and thirteen CEBPAbZIP-inf patients were identified in a cohort of 887 AML patients homogeneously treated with intensive chemotherapy. Concurrent WT1 or DNMT3A mutations significantly predicted worse survival in AML patients with CEBPAbZIP-inf. RNA-sequencing analysis revealed an enrichment of interferon (IFN) signaling and metabolic pathways in those with a shorter event-free survival (EFS). CEBPAbZIP-inf patients with a shorter EFS had higher expression of IFN-stimulated genes (IRF2, IRF5, OAS2, and IFI35). Genes in mitochondrial complexes I (NDUFA12 and NDUFB6) and V (ATP5PB and ATP5IF1) were overexpressed and were associated with poorer survival, and the results were independently validated in the TARGET AML cohort. In conclusion, concurrent WT1 or DNMT3A mutations and a dysregulated immune and metabolic state were correlated with poor survival in patients with CEBPAbZIP-inf, and upfront allogeneic transplantation may be indicated for better long-term disease control.

A case of acute myelomonocytic leukemia morphologically mimicking lymphoblastic leukemia.

We present the case of a 70-year-old man diagnosed with acute myelomonocytic leukemia, albeit that his leukemic blasts at initial presentation had scant cytoplasm, inconspicuous cytoplasmic granules, and morphologically mimicked lymphoblasts. We would like to raise the recognition that acute myelomonocytic leukemia can actually present with atypical blast morphology.

Validation of the molecular international prognostic scoring system in patients with myelodysplastic syndromes defined by international consensus classification.

Myelodysplastic syndromes (MDS) have varied prognoses and require a risk-adapted treatment strategy for treatment optimization. Recently, a molecular prognostic model (Molecular International Prognostic Scoring System [IPSS-M]) that combines clinical parameters, cytogenetic abnormalities, and mutation topography was proposed. This study validated the IPSS-M in 649 patients with primary MDS (based on the 2022 International Consensus Classification [ICC]) and compared its prognostic power to those of the IPSS and revised IPSS (IPSS-R). Overall, 42.5% of the patients were reclassified and 29.3% were up-staged from the IPSS-R. After the reclassification, 16.9% of the patients may receive different treatment strategies. The IPSS-M had greater discriminative potential than the IPSS-R and IPSS. Patients with high, or very high-risk IPSS-M might benefit from allogeneic hematopoietic stem cell transplantation. IPSS-M, age, ferritin level, and the 2022 ICC categorization predicted outcomes independently. After analyzing demographic and genetic features, complementary genetic analyses, including KMT2A-PTD, were suggested for accurate IPSS-M categorization of patients with ASXL1, TET2, STAG2, RUNX1, SF3B1, SRSF2, DNMT3A, U2AF1, and BCOR mutations and those classified as MDS, not otherwise specified with single lineage dysplasia/multi-lineage dysplasia based on the 2022 ICC. This study confirmed that the IPSS-M can better risk-stratified MDS patients for optimized therapeutic decision-making.

Poor prognostic implications of myelodysplasia-related mutations in both older and younger patients with de novo AML.

A set of myelodysplasia-related (MDS-R) gene mutations are incorporated into the 2022 European LeukemiaNet risk classification as adverse genetic factors for acute myeloid leukemia (AML) based on their poor prognostic impact on older patients. The impact of these mutations on younger patients (age < 60 years) remains elusive. In the study of 1213 patients with de novo non-M3 AML, we identified MDS-R mutations in 32.7% of the total cohort, 44.9% of older patients and 23.4% of younger patients. The patients with MDS-R mutations had a significantly lower complete remission rate in both younger and older age groups. With a median follow-up of 9.2 years, the MDS-R group experienced shorter overall survival (P = 0.034 for older and 0.035 for younger patients) and event-free survival (P = 0.004 for older and 0.042 for younger patients). Furthermore, patients with MDS-R mutations more frequently harbored measurable residual disease that was detectable using next generation sequencing at morphological CR than those without MDS-R mutations. Allogeneic hematopoietic stem cell transplantation (allo-HSCT) might ameliorate the negative impact of MDS-R mutations. In summary, AML patients with MDS-R mutations have significantly poorer outcomes regardless of age. More intensive treatment, such as allo-HSCT and/or novel therapies, is warranted for AML patients with MDS-R mutations.

Busulfan-containing conditioning regimens in allogeneic hematopoietic stem cell transplantation for acute lymphoblastic leukemia: A Taiwan observational study.

BACKGROUND: Allogeneic stem cell transplantation (allo-HSCT) is the ultimate cure for acute lymphoblastic leukemia (ALL). AIM: This study was performed to compare the outcomes of ALL patients receiving busulfan (Bu) with cyclophosphamide (Cy)-based or total body irradiation (TBI)-based regimen in a Chinese population. METHODS: We enrolled 224 adult patients with ALL who received allo-HSCT at National Taiwan University Hospital between 1997 and 2016. RESULTS: The median age at transplantation was 33 years. Before allo-HSCT, 75.9% of patients attained first or late complete remission. A total of 141 patients (62.9%) received Bu/Cy-based conditioning, either myeloablative (MA) or reduced-intensity stem cell transplantation (RIST), and 83 patients received a TBI-based regimen (MA-TBI). Patients receiving the MA-Bu regimen had longer relapse-free survival (RFS) than those receiving the MA-TBI regimen (median, 24.1 vs. 6.7 months, p = .044). There was no difference in overall survival (OS, MA-Bu vs. MA-TBI vs. RIST-Bu: 39.4 vs. 28.2 vs. 13.1 months, p = .276), treatment-related mortality (TRM), or incidences of grade 3-4 acute graft-versus-host disease (GvHD). Among patients receiving identical GvHD prophylactic regimens, there was no difference between MA-Bu and MA-TBI groups regarding the incidence of grade 3-4 acute GvHD, grade 2-4, and all-grade chronic GvHD. In subgroup analysis, patients receiving oral busulfan had comparable RFS and OS to the intravenous busulfan group (p = .436 and p = .236, respectively), but a higher TRM (25% vs. 9.8%, p = .016). In the multivariable analysis, disease status before allo-HSCT was the only risk factor impacting RFS and OS. CONCLUSION: In summary, patients receiving Bu/Cy-based or TBI-based regimens as conditioning had similar results in terms of OS, TRM, and acute GvHD, whereas the use of myeloablative Bu/Cy resulted in a better RFS. A Bu-based regimen could be an alternative conditioning choice for patients who are ineligible to receive TBI. Prospective and randomized controlled trials are warranted to validate the long-term outcomes.

Distinct clinico-biological features in AML patients with low allelic ratio FLT3-ITD: role of allogeneic stem cell transplantation in first remission.

The mutant burden of FLT3-ITD modulates its prognostic impact on patients with acute myeloid leukemia (AML). However, for patients with low allelic ratio (AR) FLT3-ITD (FLT3-ITDlow, AR < 0.5), clinical features, as well as genomic and transcriptomic profiles remain unclear, and evidence supporting allogeneic hematopoietic stem cell transplantation (allo-HSCT) in first complete remission (CR1) remains controversial. This study aimed to elucidate the genomic features, prognosis, and transplantation outcome of FLT3-ITDIow in AML patients with intermediate-risk cytogenetics. FLT3-ITDlow was associated with a negative enrichment of the leukemic stem cell signature, a marked enrichment of the RAS pathway, and with higher frequencies of RAS pathway mutations, different from those with FLT3-ITDhigh. Concurrent CEBPA double mutations were favorable prognostic factors, whereas MLL-PTD, and mutations in splicing factors were unfavorable prognostic factors in FLT3-ITDlow patients. Patients with FLT3-ITDlow had a shorter overall survival (OS) and event-free survival (EFS) than those with FLT3wt. Allo-HSCT in CR1 was associated with a significantly longer OS and EFS compared with postremission chemotherapy in patients with FLT3-ITDlow. In conclusion, FLT3-ITDlow is associated with different mutational and transcriptomic profiles compared with FLT3-ITDhigh. The presence of concomitant poor-risk mutations exert negative prognostic impacts in patients with FLT3-ITDlow, who markedly benefit from allo-HSCT in CR1.