Outcomes and adverse events in older acute lymphoblastic Leukemia patients treated with a pediatric-inspired protocol with Pegylated or native Asparaginase.

This retrospective report presents the outcomes and adverse events (AEs) observed in 73 patients aged 60 years or older diagnosed with Philadelphia Chromosome-negative Acute Lymphoblastic Leukemia (Ph-negative ALL) treated with a pediatric-inspired protocol incorporating either Pegylated (PEG-ASP) or Native Asparaginase (EC-ASP). Notably, 61% of patients experienced AEs of Grade III-IV severity. The most prevalent AEs included thrombosis (35.6%), febrile neutropenia (38.4%), and transaminitis (34.2%). AEs did not translate into significant differences concerning overall survival, leukemia-free survival, or early mortality. Furthermore, we observed a reduction in early mortality rates (11% vs. 20%) and an increase in median overall survival (54 vs. 48 months) compared to our previous data. These findings suggest that the utilization of a pediatric-inspired chemotherapy protocol, with ASP, is an effective and well-tolerated therapeutic option for older patients with Ph-negative ALL. However, it emphasizes the importance of diligent monitoring and close follow-up throughout treatment.

Clinical Features and Long-Term Outcomes of a Pan-Canadian Cohort of Adolescents and Young Adults with Myeloproliferative Neoplasms: A Canadian MPN Group Study.

Myeloproliferative neoplasms (MPNs) are a group of chronic hematologic malignancies that lead to morbidity and early mortality due to thrombotic complications and progression to acute leukemia. Clinical and mutational risk factors have been demonstrated to predict outcomes in patients with MPNs and are used commonly to guide therapeutic decisions, including allogenic stem cell transplant, in myelofibrosis. Adolescents and young adults (AYA, age ≤45 years) comprise less than 10% of all MPN patients and have unique clinical and therapeutic considerations. The prevalence and clinical impact of somatic mutations implicated in myeloid disease has not been extensively examined in this population. We conducted a retrospective review of patients evaluated at eight Canadian centers for MPN patients diagnosed at ≤45 years of age. In total, 609 patients were included in the study, with median overall survival of 36.8 years. Diagnosis of prefibrotic or overt PMF is associated with the lowest OS and highest risk of AP/BP transformation. Thrombotic complications (24%), including splanchnic circulation thrombosis (9%), were frequent in the cohort. Mutations in addition to those in JAK2/MPL/CALR are uncommon in the initial disease phase in our AYA population (12%); but our data indicate they may be predictive of transformation to post-ET/PV myelofibrosis.

Venous thromboembolism in critically ill adult patients with hematologic malignancy: a population-based cohort study.

PURPOSE: The aim of this study was to describe the incidence of venous thromboembolism (VTE) and major bleeding among hospitalized patients with hematologic malignancy, assessing its association with critical illness and other baseline characteristics. METHODS: We conducted a population-based cohort study of hospitalized adults with a new diagnosis of hematologic malignancy in Ontario, Canada, between 2006 and 2017. The primary outcome was VTE (pulmonary embolism or deep venous thrombosis). Secondary outcomes were major bleeding and in-hospital mortality. We compared the incidence of VTE between intensive care unit (ICU) and non-ICU patients and described the association of other baseline characteristics and VTE. RESULTS: Among 76,803 eligible patients (mean age 67 years [standard deviation, SD, 15]), 20,524 had at least one ICU admission. The incidence of VTE was 3.7% in ICU patients compared to 1.2% in non-ICU patients (odds ratio [OR] 3.08; 95% confidence interval [CI] 2.77-3.42). The incidence of major bleeding was 7.6% and 2.4% (OR 3.33; 95% CI 3.09-3.58), respectively. The association of critical illness and VTE remained significant after adjusting for potential confounders (OR 2.92; 95% CI 2.62-3.25). We observed a higher incidence of VTE among specific subtypes of hematologic malignancy and patients with prior VTE (OR 6.64; 95% CI 5.42-8.14). Admission more than 1 year after diagnosis of hematologic malignancy (OR 0.64; 95% CI 0.56-0.74) and platelet count ≤ 50 × 109/L at the time of hospitalization (OR 0.63; 95% CI 0.48-0.84) were associated with a lower incidence of VTE. CONCLUSION: Among patients with hematologic malignancy, critical illness and certain baseline characteristics were associated with a higher incidence of VTE.

Flow cytometry-based measurable residual disease (MRD) analysis identifies AML patients who may benefit from allogeneic hematopoietic stem cell transplantation.

Measurable residual disease (MRD) monitoring independently predicts long-term outcomes in patients with acute myeloid leukemia (AML). Of the various modalities available, multiparameter flow cytometry-based MRD analysis is widely used and relevant for patients without molecular targets. In the transplant (HCT) setting, the presence of MRD pre-HCT is associated with adverse outcomes. MRD-negative remission status pre-HCT was also associated with longer overall (OS) and progression-free survival and a lower risk of relapse. We hypothesize that the combination of disease risk and MRD at the time of first complete remission (CR1) could identify patients according to the benefit gained from HCT, especially for intermediate-risk patients. We performed a retrospective analysis comparing the outcomes of HCT versus non-HCT therapies based on MRD status in AML patients who achieved CR1. Time-dependent analysis was applied considering time-to-HCT as a time-dependent covariate and compared HCT versus non-HCT outcomes according to MRD status at CR1. Among 336 patients assessed at CR1, 35.1% were MRD positive (MRDpos) post-induction. MRDpos patients benefitted from HCT with improved OS and relapse-free survival (RFS), while no benefit was observed in MRDneg patients. In adverse-risk patients, HCT improved OS (HR for OS 0.55; p = 0.05). In intermediate-risk patients, HCT benefit was not significant for OS and RFS. Intermediate-risk MRDpos patients were found to have benefit from HCT with improved OS (HR 0.45, p = 0.04), RFS (HR 0.46, p = 0.02), and CIR (HR 0.41, p = 0.02). Our data underscore the benefit of HCT in adverse risk and MRDpos intermediate-risk AML patients.

Outcomes of intensive and nonintensive blast-reduction strategies in accelerated and blast-phase MPN.

ABSTRACT: Transformation of BCR::ABL1-negative myeloproliferative neoplasms (MPN) to an accelerated or blast phase is associated with poor outcomes. The efficacy of acute myeloid leukemia (AML)-type intensive and nonintensive hypomethylating agent-based regimens is not well studied. We therefore performed a retrospective analysis of patients with MPN-AP/BP (N = 138) treated with intensive (N = 81) and nonintensive (N = 57) blast-reduction strategies. We used clinically relatable response criteria developed at the Princess Margaret Cancer Centre. The overall best response, comprising complete remission (CR), complete remission with incomplete hematologic recovery (CRi), and reversion to chronic phase MPN (cMPN), in the intensive and nonintensive groups was 77% (62 of 81) and 39% (21 of 54), respectively. Similar overall best response rates were observed in patients receiving induction with daunorubicin combined with cytarabine arabinoside (daunorubicin + ara-C) (74% [23 of 31]) or FLAG-IDA/NOVE-HiDAC (78% [39 of 50], P = .78). However, patients receiving daunorubicin + ara-C more often required second inductions (29% [9 of 31] vs 4% [2 of 50], P = .002). Most responses in the entire cohort were reversions to cMPN (55 of 83 [66%]). CR and CRi comprised 30% (25 of 83) and 4% (3 of 83) of responses, respectively. Mutations in TP53 (overall response [OR] 8.2 [95% confidence interval [CI] 2.01, 37.1], P = .004) and RAS pathway (OR 5.1 [95%CI 1.2, 23.7], P = .03) were associated with inferior treatment response for intensively treated patients, and poorer performance status (Eastern Cooperative Oncology Group) was associated with inferior treatment response in both intensively (OR 10.4 [95% CI 2.0, 78.5], P = .009) and nonintensively treated groups (OR 12 [95% CI 2.04, 230.3], P = .02). In patients with paired samples before and after therapy (N = 26), there was a significant residual mutation burden remaining irrespective of response to blast-reduction therapy.

Upfront allogeneic transplantation versus JAK inhibitor therapy for patients with myelofibrosis: a North American collaborative study.

Allogeneic hematopoietic cell transplantation (HCT) is the only curative therapy for myelofibrosis (MF) and is recommended for patients with higher risk disease. However, there is a risk of early mortality, and optimal timing is unknown. JAK inhibitor (JAKi) therapy may offer durable improvement in symptoms, splenomegaly and quality of life. The aim of this multicentre, retrospective observational study was to compare outcomes of patients aged 70 years or below with MF in chronic phase who received upfront JAKi therapy vs. upfront HCT in dynamic international prognostic scoring system (DIPSS)-stratified categories. For the whole study cohort, median overall survival (OS) was longer for patients who received a JAKi vs. upfront HCT, 69 (95% CI 57-89) vs. 42 (95% CI 20-not reached, NR) months, respectively (p = 0.01). In patients with intermediate-2 and high-risk disease, median OS was 55 (95% CI 36-73) months with JAKi vs. 36 (95% CI 20-NR) months for HCT (p = 0.27). An upfront HCT strategy was associated with early mortality and difference in median OS was not observed in any risk group by 5 years of follow-up. Within the limitations of a retrospective observational study, we did not observe any benefit of a universal upfront HCT approach for higher-risk MF.

Preclinical characterization and clinical trial of CFI-400945, a polo-like kinase 4 inhibitor, in patients with relapsed/refractory acute myeloid leukemia and higher-risk myelodysplastic neoplasms.

CFI-400945 is a selective oral polo-like kinase 4 (PLK4) inhibitor that regulates centriole duplication. PLK4 is aberrantly expressed in patients with acute myeloid leukemia (AML). Preclinical studies indicate that CFI-400945 has potent in vivo efficacy in hematological malignancies and xenograft models, with activity in cells harboring TP53 mutations. In this phase 1 study in very high-risk patients with relapsed/refractory AML and myelodysplastic syndrome (MDS) (NCT03187288), 13 patients were treated with CFI-400945 continuously in dose escalation from 64 mg/day to 128 mg/day. Three of the 9 efficacy evaluable AML patients achieved complete remission (CR). Two of 4 AML patients (50%) with TP53 mutations and complex monosomal karyotype achieved a CR with 1 patient proceeding to allogenic stem cell transplant. A third patient with TP53 mutated AML had a significant reduction in marrow blasts by > 50% with an improvement in neutrophil and platelet counts. Responses were observed after 1 cycle of therapy. Dose-limiting toxicity was enteritis/colitis. A monotherapy and combination therapy study with a newer crystal form of CFI-400945 in patients with AML, MDS and chronic myelomonocytic leukemia (CMML) is ongoing (NCT04730258).

Biallelic disruption of DDX41 activity is associated with distinct genomic and immunophenotypic hallmarks in acute leukemia.

Introduction: Inherited DDX41 mutations cause familial predisposition to hematologic malignancies including acute myeloid leukemia (AML) and myelodysplastic syndromes (MDS), with the majority of DDX41 mutated MDS/AMLs described to date harboring germline DDX41 and co-occurring somatic DDX41 variants. DDX41-AMLs were shown to share distinguishing clinical features such as a late AML onset and an indolent disease associated with a favorable outcome. However, genotype-phenotype correlation in DDX41-MDS/AMLs remain poorly understood. Methods: Here, we studied the genetic profile, bone marrow morphology and immunophenotype of 51 patients with DDX41 mutations. We further assessed the functional impact of ten previously uncharacterized DDX41 variants of uncertain significance. Results: Our results demonstrate that MDS/AML cases harboring two DDX41 variants share specific clinicopathologic hallmarks that are not seen in other patients with monoallelic DDX41 related hematologic malignancies. We further showed that the features seen in these individuals with two DDX41 variants were concordant with biallelic DDX41 disruption. Discussion: Here, we expand on previous clinicopathologic findings on DDX41 mutated hematologic malignancies. Functional analyses conducted in this study unraveled previously uncharacterized DDX41 alleles and further illustrate the implication of biallelic disruption in the pathophysiology of this distinct AML entity.

Impact of Geographical Distance from Quaternary Treatment Center on Clinical Trial Participation, Intensive Induction Chemotherapy, and Outcomes in Patients with Newly Diagnosed Acute Myeloid Leukemia.

INTRODUCTION: Care for patients with acute myeloid leukemia (AML) is centralized in the Ontario single-payer public healthcare system, with intensive induction chemotherapy and clinical trials only offered at specialized cancer centers with large catchment areas. METHODS: We therefore conducted a retrospective single-center review of all AML patients assessed at a large specialized cancer center in Ontario, Canada. RESULTS: Between 2012 and 2017, 1,310 patients were assessed by our center for upfront AML therapy. The median distance was 33.1 km, with 29% of patients living more than 50 km away from the center. There was no significant difference in probability of intensive induction chemotherapy or clinical trial by distance from center, both in univariate and multivariable analysis adjusting for age, sex, cytogenetics and molecular testing, and performance status. There was no significant difference in overall survival by distance from center on univariate and multivariable analysis. CONCLUSION: In conclusion, geographic distance from treatment center does not appear to impact choice of upfront therapy, participation in clinical trials, or clinical outcomes in this study of newly diagnosed patients with AML treated in a single-payer environment.

Safety of re-challenging adults with acute lymphoblastic leukemia with PEG-asparaginase-induced severe hypertriglyceridemia when treated with a pediatric-inspired regimen.

PEG-asparaginase is used as a treatment for Philadelphia-negative acute lymphoblastic leukemia. In pediatric studies, triglycerides (TGs) were affected more by PEG-asparaginase than by native L-asparaginase (10.0% vs. 5.5%). We conducted a retrospective study to determine the safety of re-challenging adult patients with PEG-asparaginase after experiencing an episode of severe hypertriglyceridemia (>1000 mg/dl or 11.4 mmol/L). The incidence of hypertriglyceridemia associated with PEG-asparaginase in adult patients was high (67.5%). Therefore, checking TGs at baseline and monitoring levels while receiving PEG-asparaginase need to be considered and studied in prospective studies. However, in patients with hypertriglyceridemia not complicated by acute pancreatitis, re-challenging is safe once TG levels normalize.

Improved donor chimerism in relapse myelofibrosis post allogenic stem cell transplant with azacitidine and oral decitabine-First case report.

To date, allogenic stem cell transplant (ASCT) remains the only potential curative option for patients with primary myelofibrosis (PMF). However, relapse rates and associated mortality remain a concern. A second ASCT may not be feasible due to advancing age, declined functional status, donor unavailability, toxicities associated with a second ASCT. Herein, we report the first case of utilizing initially azacitidine and subsequently oral decitabine + cedazuridine (decitabine), in the context of relapsed PMF post-ASCT. Utilizing both hypomethylating agents provided disease control and improved donor/myeloid lineage chimerism levels, and the patient also remained transfusion independent, with preserved functional status and quality of life.

Venous thromboembolism incidence associated with pegylated asparaginase (ASP) compared to the native L-ASP: A retrospective analysis with an ASP-based protocol in adult patients with acute lymphoblastic leukaemia.

Venous thromboembolism (VTE) is a well-known complication in patients with acute lymphoblastic leukaemia (ALL) receiving asparaginase (ASP)-based chemotherapy, including the ASP-intensive Dana-Farber Cancer Institute (DFCI) 91-01 protocol for adults. Since 2019, native L-ASP is no longer available in Canada and was replaced by pegylated (PEG)-ASP. To determine whether the incidence of VTE has changed since switching from L-ASP to PEG-ASP, we conducted a single-centred retrospective cohort study. We included 245 adult patients with Philadelphia chromosome negative ALL between 2011 and 2021, with 175 from the L-ASP group (2011-2019) and 70 from the PEG-ASP group (2018-2021). During Induction, 10.29% (18/175) of patients who received L-ASP developed VTE, whereas 28.57% (20/70) of patients who received PEG-ASP developed VTE (p = 0.0035; odds ratio [OR] 3.35, 95% confidence interval [CI] 1.51-7.39), after adjusting for line type, gender, history of VTE, platelets at diagnosis. Similarly, during Intensification, 13.64% (18/132) of patients had VTE on L-ASP while 34.37% (11/32) of patients on PEG-ASP developed VTE (p = 0.0096; OR 3.96, 95% CI 1.57-9.96 with multivariable analysis). We found that PEG-ASP is associated with a higher incidence of VTE compared to L-ASP, both during Induction and Intensification, despite the administration of prophylactic anticoagulation. Further VTE mitigation strategies are needed in particular for adult patients with ALL receiving PEG-ASP.

Mutational profile, outcomes, and impact of allogeneic hematopoietic stem cell transplantation in adult patients with acute myeloid leukemia and inconclusive cytogenetic analysis.

BACKGROUND: Inconclusive cytogenetic analysis (IC) at baseline has been reported as a predictor of poor prognosis in patients with acute myeloid leukemia (AML). The mutational profile in this group of patients, and its impact on outcomes have not been reported. METHODS: We retrospectively analyzed adult patients (≥18 years) with newly diagnosed AML treated with intensive induction chemotherapy between 2015 and 2019. Patients with any documented cytogenetic abnormalities were excluded. Targeted next generation sequencing (NGS) was performed in all patients. Baseline characteristics, mutation profile, and outcomes were compared between patients with normal cytogenetics(NC) and those with IC. RESULTS: Sixty-one patients (males 39.3%; median age 59 years) had IC at diagnosis. The proportion of patients with mutations in genes with proven prognostic impact were not different between AML patients with IC and NC. AML patients with NC were more likely to harbor the prognostically favorable NPM1mut /FLT3-ITDwt mutational combination conferring "favorable" risk status. As a result, a larger proportion of patients in the IC group underwent allogeneic hematopoietic stem cell transplantation (allo HCT; 54.1% vs. 39.6%; p = .02). The 2-year RFS (55.9% vs. 58.5%; p = .29) and OS (61.9% vs. 66.9%; p = .48) were similar in IC and NC patients. There was no difference in survival of patients who underwent allo HCT when compared with patients who did not (p = .99). CONCLUSIONS: Inconclusive cytogenetic analysis may not be an independent prognostic indicator in AML. In such patients, molecular abnormalities detected through NGS or whole genome sequencing are more likely to be informative.

Foot gangrene following Tagraxofusp treatment for blastic plasmacytoid dendritic cell neoplasm: Case report.

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare and aggressive hematologic malignancy. It is associated with poor prognosis and heterogenous presentation. The CD123-directed cytotoxin, Tagraxofusp, is a targeted therapy for BPDCN. Here, we report an 81-year-old female diagnosed with BPDCN. The patient was treated with Tagraxofusp and underwent a remarkably long remission (>20 months) without stem-cell transplantation. She, however, experienced blue toe syndrome and left foot gangrene. We postulate that these previously unreported side effects were caused by microembolization. Characterization of the incidence of thrombo- and microembolizations in such a context, as well as prophylactic management options, are warranted.

Clinical implementation of genetic testing in adults for hereditary hematologic malignancy syndromes.

PURPOSE: As research on hereditary hematologic malignancy syndromes (HHMS) are accumulating, cancer genetics clinics are identifying more adult hematology patients with an inherited component to their disease. However, investigations for HHMS are complex, and there is no formal consensus on genetic testing criteria. METHODS: We developed genetic testing criteria for adult hematology patients through a comprehensive literature review and our experience at the Princess Margaret Cancer Centre. We validated our criteria by applying them retrospectively to patients referred to our clinic for HHMS assessment. RESULTS: Our genetic testing criteria are comprehensive of myeloid malignancies, lymphoid malignancies, and bone marrow failure, including age at diagnosis, family history, and genetic test results in blood and bone marrow. Of the 104 patients who met the criteria, 26% had at least 1 actionable variant in any gene associated with an increased risk of cancer and 13% had an actionable variant resulting in an HHMS diagnosis. A total of 15 patients had incidental findings, including 11 patients with a pathogenic variant associated with carrier status for an autosomal recessive disorder and 4 patients with a mosaic result. CONCLUSION: Our high gene positivity rate shows the utility of a broad approach to germline testing in an adult hematology population.