Peripheral Blast Percentage Research Articles

Changes in White Blood Cell Counts Early during Treatment of Acute Leukemia Using Differentiating Chemotherapies

Background: Differentiation syndrome (DS) is a life-threatening complication that can occur with a number of therapies used for the treatment of acute myeloid leukemia (AML). It is best characterized in patients treated with All-trans retinoic acid (ATRA) and Arsenic for acute promyelocytic leukemia (APL), or for patients receiving an IDH inhibitor for IDH1/2 mutant AML, but can also be seen with other therapies such as with FLT3 inhibitors, and in novel therapies under development such as menin inhibitors. It is critical to identify DS early, as corticosteroids can mitigate complications. The diagnosis of DS is made by recognizing a constellation of symptoms, typically including a rising white blood cell count, peripheral edema, rash, shortness of breath, pulmonary edema, and fevers. We evaluated white blood cell (WBC) count changes during treatment according to whether patients DS or not on chemotherapy. Methods: We identified adult patients who received ATRA+Arsenic for newly diagnosed APL, as well as patients with AML harboring a mutation in IDH1 or IDH2 who were treated with monotherapy IDH inhibitors (enasidenib or ivosidenib) at any point during their treatment for active AML and treated at MGH. Patients were treated at MGH between 2015 and 2023. Patients were 18 or older and had a confirmed pathological diagnosis. We interrogated the medical record to identify patients with clinical documentation of DS during treatment, as well as the treatments used for management and clinical complications. Descriptive statistics were used to identify differences in median WBC counts between patients with DS and those without DS, and comparisons were made using Wilcoxon or chi square testing as appropriate. Results: We identified 33 patients with APL who received ATRA+Arsenic, and 35 patients with AML harboring an IDH1/2 mutation treated with monotherapy IDH inhibition. Our analysis revealed that 26% (18/68) of patients had clinical documentation of differentiation syndrome, including 21% (14/33) of patients treated with ATRA+Arsenic and 11% (4/35) of patients on IDH inhibitors. In APL, the median day of a recorded diagnosis of DS was 4 days after treatment start (range 1-14 days). Patients with APL who developed DS had a higher initial WBC at treatment start compared to those who did not develop DS (6.7 vs 1.05 K/uL, p=0.03). There was no difference in hemoglobin, platelets, ANC, and percentage of peripheral blood blasts (Table 1). The WBC in DS patients started rising during the first week of treatment and peaked on Day 15 (Figure 1). Regarding treatment approaches for DS, the majority of patients were treated with steroids, (78%, 11/14) while 43% (6/14) received cytoreduction, most commonly with gemtuzumab. In IDH-mutant AML, the median day of a recorded diagnosis of DS was 35 days after treatment start (range 16-69 days). Patients with IDH-mutated AML on IDH Inhibitor monotherapy who experienced DS had a similar finding of an early temporal rise in WBC to those with APL on ATRA+Arsenic, although this rise started on day 12 and peaked on day 16 of monotherapy. Of note, these peaks occurred prior to the documentation of a clinical DS diagnosis. In contrast to APL, patients with IDH-mutant AML who developed DS had a lower baseline ANC (p=0.03) and higher percentage of peripheral blasts circulating than those without DS (p=0.03). All patients with IDH inhibitor associated DS received dexamethasone. Discussion: Patients with DS during treatment for APL on ATRA+Arsenic, as well as patients with DS with IDHmut AML on IDH inhibitors, had similar early peaks in the WBC count, occurring around 2 weeks from the start of treatment. In this small group, the IDHmut AML showed a rise in WBC that preceded the actual DS diagnosis. Understanding the timing of and risk factors for DS may help to identify at risk patients early for mitigation strategies.

TP53-Mutated Acute Myeloid Leukemia Patients Treated with Intensive Therapies Have Superior Outcomes: A Single Institution, Retrospective Study

Background: Mutations in TP53, found in 5-20% of acute myeloid leukemia (AML), confer poor prognosis and are associated with high rates of therapy resistance, high relapse rates, and dismal overall survival (OS). Recent advances have provided a variety of options for up-front AML therapy including a liposomal preparation of standard-of-care chemotherapy (CPX-351) and venetoclax-based combinations. Due to known poor outcomes with intensive chemotherapy, many providers are favoring less intense strategies for patients with TP53 mutant AML, but these approaches have not been directly compared for this patient subgroup. Strategies for treating TP53 mutant AML are highly heterogeneous and optimal treatment strategies have not been defined in this setting. We performed a retrospective study to compare the clinical outcomes of TP53 mutant AML patients treated at our center. Methods: The study was a single-center, retrospective cohort analysis conducted at the University of Minnesota. Adult patients (age ≥18 years) with the diagnosis of AML or myeloid sarcoma between January 1, 2014 and July 31, 2022 who have next-generation sequencing panel confirming a pathogenic TP53 mutation and received front-line therapy for AML at our center were included in this study. Kaplan-Meier analysis was used to estimate the probabilities of OS, defined as the date of treatment initiation to the date of death from any cause or last follow-up. Results: Our study includes 88 patients with TP53 mutant AML with available clinical data in an AML registry at our institution. Baseline demographic and clinical characteristics are summarized in Table 1. The median age at diagnosis was 67 years (range 28-87) with male predominance (65.9%). Among this, 15/88 patients (17.1%) had therapy-related AML and 40/88 patients (45.5%) had secondary AML. The median bone marrow blast percentage at diagnosis was 31% and peripheral blast percentage was 9%. The majority of patients have high variant allelic frequency (VAF, 71.9% with VAF > 0.4 for patients with available VAF data) and ASXL1 was the most frequent co-mutation identified followed by KRAS and NRAS. Treatment regimens were classified as intensive or nonintensive. Intensive treatment regimens included infusional cytarabine with either daunorubicin or idarubicin (7+3), liposomal cytarabine and daunorubicin (CPX-351), and mitoxantrone, etoposide and cytarabine (MEC). Nonintensive regimens included hypomethylating agents (decitabine or azacitidine) with or without venetoclax and clofarabine with low-dose subcutaneous cytarabine. A total of 66 patients were included in the survival analysis. There was no significant difference in OS between patients aged < 65 years and ≥ 65 years at diagnosis (2-year OS, 11% versus 5%, P=0.76). Superior 2-year OS was observed in patients who received front-line intensive (n = 31) versus nonintensive (n = 35) induction chemotherapy (2-year OS, 13% versus 3%, P=0.01, Figure 1). Patients who received intensive therapy for any line of treatment also demonstrated superior OS compared to those who never received intensive therapy (2-year OS, 12% versus 3%, P=0.02). The rate of achieving complete remission (CR) was higher in patients who received intensive treatment compared to non-intensive therapy in the first-line (51.6% versus 25.7%, P=0.03). Rate of CR at any time was also higher for patients who received intensive treatment for any line of treatment (50% versus 18.2%, P<0.01). Among the intensive first-line treatment group, 7+3 (n = 18) showed superior OS relative to CPX-351 (n = 12) (2-year OS, 22% versus 0%, P=0.03) although there was no significant difference in CR rate (55.6% versus 50%, P=0.77). Furthermore, significant survival benefit was shown in patients who underwent allogeneic hematopoietic cell transplantation compared to patients who had not (2-year OS, 21% versus 4%, P<0.01]). Conclusions: In our cohort, TP53 mutant AML patients treated with intensive chemotherapy and transplant have superior outcomes to those who do not. Since this was a retrospective study, we cannot rule out the possibility that these results are confounded by providers favoring more intensive therapies for fitter patients. However, these data imply that TP53 mutant patients may benefit from more intensive therapy and suggests that future work to define optimal therapy regimens in this patient population may incorporate intensive strategies.

British Columbia Experience in Allogeneic Stem Cell Transplantation for Myelofibrosis with or without Pre-Transplant Ruxolitinib

Introduction Allogeneic stem cell transplantation (AlloHSCT) remains the only potentially curative treatment for myelofibrosis (MF). It confronts many challenges stemming from the older age of the typical patients and their age-related comorbidities, as well as disease-specific factors such as splenomegaly and hostile marrow microenvironment, which raise concerns for delayed engraftment and graft failure. Methods We performed a retrospective review of the 58 adult patients who received AlloHSCT for MF in British Columbia, Canada, in the 20-year period between January 2001 and December 2020. Data pertaining to patient demographics, disease characteristics, treatment/transplant details and clinical outcomes were gathered from the available paper and electronic records. Relapse-free survival (RFS) was defined as the time between the day of the transplant and the day of disease relapse or death from any cause. Overall survival (OS) was defined as the time between the day of the transplant and death from any cause. Patients who did not have an event during follow up were censored at the time of the last known follow up. Survival analysis was performed by Kaplan-Meier survival estimator and log-rank test, using Stata version 16.1 (Texas, USA). Results The median age of the cohort was 56 years (range 26-68), with 36% being 60 years old or older. The male to female ratio was 1.6:1. The median Karnofsky Performance Status index was 80 (range 70-100) and the median age-adjusted HCT-specific Comorbidity Index was 2 (range 0-5). The pre-transplant DIPPS plus risk category was: high in 13 patients (22%); intermediate-2 in 29 (50%); intermediate-1 in 15 (26%); and low in 1 (2%). 19/58 (33%) had a peripheral blast percentage greater than 2%. 51/58 (88%) had grade 3 fibrosis seen on the pre-AlloHSCT bone marrow biopsy. 27/57 (47%) patients were transfusion-dependent for pRBC and/or platelets. 28/54 (52%) evaluable patients had a normal karyotype and 6/54 (11%) a complex karyotype. Sixteen patients (28%) had a myeloid gene panel performed by PCR; the most commonly seen variants were ASXL1 (10 patients) and TET2 (5 patients). The median number of variants seen in a single patient was 3 (range 0-5). 42/58 (72%) patients received myeloablative conditioning before AlloHSCT. The donor type was: a volunteer unrelated donor in 54%; a matched sibling in 42%; and an alternative source (double cord or haploidentical donor) in 4%. Peripheral blood stem cells were used in 93% of the AlloHSCT. 24/58 (41%) patients received ruxolitinib pre-AlloHSCT (starting in June 2012) for a median duration of 10 months (range 1-44); 17/24 (71%) of the recipients had a clinical response to ruxolitinib but 3 had lost the response before their AlloHSCT. One patient had stopped ruxolitinib due to cytopenia. During a median follow up period of 41.7 months (range 0.5-260.7), 24/58 (41%) experienced acute graft-versus-host disease (GVHD) and 33/49 (67%) evaluable patients developed chronic GVHD. Graft failure was seen in 2 patients - one primary and the other secondary. MF relapse was seen in 13/58 (22%) after a median time of 1.1 years post-AlloHSCT (IQR 0.7-2.4). The transplant-related mortality (TRM) was 25% at 1 year and 28% at 3 years post-AlloHSCT. The most common causes of death were infection (7 patients), disease relapse (6 patients), and multiorgan failure (5 patients). Transfusion independence was achieved in 45/58 (78%) patients by day +100 and in 40/44 (90%) by 1-year post-AlloHSCT. 17/48 (35%) evaluable patients had persistent grade 3 fibrosis on their day+100 bone marrow biopsy. The estimated 1-year, 5-year and 10-year RFS rates were 66% (95% CI 52-76), 55% (95% CI 41-67) and 47% (95% CI 42-61) respectively. The estimated 1-year, 5-year and 10-year OS rates were 72% (95% CI 59-82), 63% (95% CI 49-74) and 54% (95% CI 37-68) respectively. There were no differences in RFS (p=0.40) and OS (p=0.23) between those who received ruxolitinib pre-transplant vs. those who did not. Conclusion In our cohort, approximately half the AlloHSCT recipients achieved long-term survival, many in remission (10-year OS 54%; 10-year RFS 47%). TRM was seen in 25% within the first year after AlloHSCT, with patients most commonly succumbing to infections. The graft failure rate was low at 3%. An increasing number of patients received pre-AlloHSCT ruxolitinib in the recent years but we were unable to demonstrate improved transplant outcomes with its use in this single centre cohort.

Preliminary Results from a Phase 1 Dose Escalation Study of FHD-286, a Novel BRG1/BRM (SMARCA4/SMARCA2) Inhibitor, Administered As an Oral Monotherapy in Patients with Advanced Hematologic Malignancies

The BRG/Brahma-associated factors (BAF) family of chromatin remodeling complexes (also referred to as the mSWI/SNF complex) regulates the chromatin landscape of the genome. Through its adenosine triphosphate (ATP)-dependent chromatin remodeling activity, BAF complexes regulate the accessibility of gene-control elements, allowing for the binding of transcription factors. Thus, BAF is a major regulator of lineage- and disease-specific transcriptional programs. FHD-286 is a first-in-class, orally administered compound that potently and selectively inhibits the ATPase components of the BAF complexes, SMARCA4 and SMARCA2 (also called BRG1 and BRM, respectively). In preclinical models, acute myeloid leukemia (AML) cell lines were highly sensitive to BAF inhibition. FHD-286-C-002 (NCT04891757) is a multicenter, open-label, Phase 1 dose escalation study designed to determine the safety, tolerability, dose-limiting toxicities (DLTs), and maximum tolerated dose and/or the recommended phase 2 dose(s), as well as to evaluate the preliminary clinical activity of FHD-286, in patients with advanced hematologic malignancies. Patients with relapsed or refractory (R/R) AML or myelodysplastic syndrome (MDS) failing all available standard therapies were eligible to receive FHD-286 doses ranging from 2.5 mg once daily (QD) to 10 mg QD on a continuous dosing regimen. Patients had regularly scheduled assessments to evaluate safety, pharmacokinetics (PK), pharmacodynamics, preliminary clinical activity, and exploratory biomarkers. As of 02 Aug 2022, 40 patients with a median age of 65.5 years (range 25 to 84) with R/R AML (36 patients) or MDS (4 patients) had received at least 1 dose of FHD-286. 67.5% of patients had received ≥3 prior lines of therapy for AML/MDS/other antecedent hematologic disorder, with 22.5% having received ≥5 prior lines. 32.5% of patients had prior hematopoietic stem cell transplant. 65% of patients had adverse risk genetics by 2017 ELN recommendations. 85% of patients experienced a treatment-related adverse event (TRAE) of any grade; the most common (≥20% of patients) were dry mouth (27.5%), increased blood bilirubin (22.5%), and alanine aminotransferase (ALT) increased and rash (20% each). 50% of patients experienced a Grade ≥3 TRAE, the most common of which was increased blood bilirubin (12.5%); stomatitis, ALT increased, differentiation syndrome (DS), and hypocalcemia occurred in 7.5% (each). 2 DLTs were reported: Grade 3 hyperbilirubinemia in 1 patient receiving 5 mg QD and Grade 3 muscular weakness in 1 patient receiving 10 mg QD. Treatment-related DS of any grade was investigator-reported in 4 patients (10%). An independent adjudication committee determined that the rate of suspected DS was 15% (6 patients). 16 patients (15 AML; 1 MDS) had a best overall response of stable disease. Markers of myeloid differentiation with neutrophil recovery and reductions in bone marrow and/or peripheral blasts have been observed in a subset of patients in the study who had a broad range of cytogenetic backgrounds, including patients with enhancer-driven leukemias such as MECOM and KMT2A. Preliminary PK analysis indicates that FHD-286 appears to have a long half-life, at a minimum of >24 hours, and that plasma concentrations of FHD-286 increase with increasing dose. Exploratory flow cytometry assessment of markers of differentiation, hematopoietic stem cell identity, and apoptosis suggested dose-dependent target engagement. Additionally, exploratory sequencing analysis on bone marrow blasts revealed comprehensive impacts on AML-specific expression pathways and stemness genes in response to FHD-286. An exposure-response analysis using the percentage of peripheral blasts showed a trend toward lower blast count with higher FHD-286 area-under-the-curve. Enrollment into the single-agent dose escalation phase of the study is complete. Based on nonclinical, translational, and single-agent clinical data, FHD-286 in combination with decitabine or low-dose cytarabine is being evaluated in the combination dose escalation phase of the study.

FLT3 Gene Mutations in Acute Myeloid Leukemia Patients in Northeast Thailand.

BACKGROUND Mutations in the FLT3 gene are associated with acute myeloid leukemia (AML). FLT3 mutations have been identified in approximately 30% of de novo AML patients, particularly those with typical karyotype and inferior prognosis. Therefore, we examined the frequencies of an internal tandem duplication (ITD) and missense mutations of the FLT3 gene and their associated clinical characteristics in patients with AML in northeast Thailand. MATERIAL AND METHODS The leftover bone marrow and/or peripheral blood specimens of 65 newly diagnosed AML patients recruited from Srinagarind Hospital, Khon Kaen University, northeast Thailand, between January 2020 and May 2021 were included in this study. FLT3-ITD and FLT3- tyrosine kinase domain (TKD) were amplified using PCR-related techniques. RESULTS The frequencies of FLT3-ITD and TKD were found to be 16.9% (11/65) and 10.8% (7/65), respectively. One patient had ITD and TKD mutations. The white blood cell count and peripheral blast percentage of FLT3-ITD-positive patients were statistically significantly higher than those of the FLT3-wild type patients, while the peripheral blast percentage of FLT3-TKD-positive patients was significantly lower. No other clinical characteristics among FLT3-positive and FLT3-wild-type patients were observed. DNA sequencing identified 4 FLT3-TKD mutations. The c.2504A>T; Asp835Val and c.2503G>C; Asp835His mutations were predicted as pathogenic mutations while the 2 novel mutations, c.2508C>A; Ile836= and c.2508C>G; Ile836Met were predicted as neutral mutations. CONCLUSIONS This study showed for the first time that FLT3-TKD mutation is common among northeast Thai AML patients. The data should prove useful for selecting efficacious targeted treatment plans for the patients.

Role of MBD4 Mutation in Neoplastic Evolution of Acute Myeloid Leukemia

Unlike pediatric cases, adult patients with myeloid neoplasia (MN) are less often suspected to harbor germline (GL) driver or predisposition alterations. However, recent discoveries of various genes affected by GL alterations linked to long disease anticipation and incomplete penetrance indicate a growing role of familial predisposition in adult MN including, the impact of heterozygous alleles within recessive traits, biallelic (GL/somatic) or compound heterozygous (GL/GL and GL/somatic) configurations of various genes. Recently, genomic profiling of 3 early-onset AMLs identified MBD4 GL loss as an initiator of 5-methylcytosine (5mC)-dependent hypermutation with a 33-fold higher mutational burden (>95% being C>T in the context of a CG)1. In cases from our institution, a biallelic MBD4 c.1291C>T, p.Arg431* & c.1688T>A p.Leu563* (in trans) tracked with AML in brother and sister2. MBD4 is a known DNA glycohydrolase involved in DNA mismatch repair (MMR) essential for reducing genotoxic stress in normal cells. Loss of function mutation in MBD4 may result in compromised MMR leading to genomic instability. MBD4 binds to 5mC and 5-hydroxymethylcytosine (5hmC), oxidation products of TET2 dioxygenases, and initiates a multi-step MMR around methylated CpG DNA. Therefore, we hypothesized that loss of MBD4 may result in reduced MMR leading to increased genomic instability and acquisition of additional lesions which may facilitate clonal evolution. We first analyzed data from 1,692 MN patients (732 MDS and 960 AML) and found 134 (8%) patients with 22 MBD4 variants. Overall, 20 were non-synonymous missense (in 132 pts), while nonsense and frameshift deletion were also observed in 1 case each. After variant filtering and annotation, we retained 17 recurrent missense in 80 patients and 1 nonsense variant in 1 patient at an odds ratio of >1.5 vs. healthy control, for a total of 81 patients harboring MBD4 VUS (Fig.1A). Among them, 4 variants (p.Arg83His, p.Asp107Tyr, p.Ser135Ala, p.Arg149Ser) mapped within the methyl-CpG-binding domain, whereas 5 variants (p.Arg425Gln, p.Asn461Ser, p.Arg486Lys, p.Asp504His, p.Asp562His) were located in the glycosylase domain (Fig.1B). Of note is that all cases were heterozygous. Comparing MBD4MTvs.MBD4WT cases, there was no significant difference in age (median was 69 vs. 71 yrs), diagnosis, clinical parameters (WBC, ANC, Hb, Plt counts, peripheral and bone marrow blast percentage) and past history of malignancy. When we compared the somatic genotype of MBD4 VUS carriers vs. carriers of MBD4WT, somatic TET2 hits were found with a significantly lower frequency (15 vs. 25%, P=.046), in particular in AML (7 vs. 22%, P=.009) and in cases with TET2 truncations (9 vs. 19%, P=.018). To further investigate the biochemical basis of MBD4 dysfunction, and its connection to TET2 DNA dioxygenases, we knocked out MBD4 in TET2 mutant and in isogenic control cell lines. To test if the DNA hydrolase activity impacts on genomic accumulation of 5hmC in TET2-dependent manner, we assessed the impact of MBD4 loss on DNA methylation using 5mC and 5hmC ratio as read out in MBD4KO and WT cells in TET2MT and isogenic controls. Our results show that the loss of MBD4 resulted in increased 5hmC compared with the isogenic WT cells when accompanied with TET2WT but this effect was absent in TET2KO cells (mean fold change, 1.9±0.4 vs. 0.9±0.1; P=.03), suggesting a cross talk between MBD4 and TET2. Consequently, in agreement with our hypothesis, TET2WT cells with loss of MBD4 were significantly more sensitive to olaparib-mediated PARP1 inhibition. We also performed the RNA-seq analysis of MBD4WT and KO cells in the presence and absence of functional TET2. These results demonstrate that MBD4 variant carrier status may be a predisposition factor for the development of MN. As loss of MBD4 mimicked the loss of TET-dioxygenase function, MBD4 could function downstream of TET2 converting 5mC to 5hmC and to cytosine as a DNA damage repair associated protein (Fig. 1C). Our findings pave the way for consideration of MBD4 as a potential actionable target to regulate DNA methylation in association with TET2 during leukemogenesis. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Characteristics and Outcomes for Adult Patients with T-Lymphoblastic Leukemia/Lymphoma (T-ALL/LBL): A Retrospective Study

Introduction T-lymphoblastic leukemia/lymphomas (T-ALL/LBL) are immature T-lymphoid neoplasms localizing in the bone marrow, mediastinum, central nervous system, and lymphoid organs. T-ALL/LBL accounts for 10 - 15% of pediatric and 25% of adult acute lymphoblastic leukemia (ALL) cases. Historically, the outcome of adult patients with newly diagnosed T-ALL/LBL) has been poor. Various studies reported low complete remission (CR) rates and short median overall survival (OS) ranging from 11 to 17 months. Here we present real-world data on outcomes and characteristics of an ethnically diverse adult population with T-ALL/LBL treated in a large academic center. Methods A retrospective chart review was performed of all patients with pathologic diagnosis of T-ALL/LBL at Los Angeles County + University of Southern California Medical Center and Norris Comprehensive Cancer Center. We identified thirty-one patients between January 1st, 2011 and January 1st, 2020. Demographic, clinical, and pathologic data were extracted from the medical record. Data analysis software SAS (9.4) was used to assess overall survival (OS). Results In our cohort, 61% were male and 55% were Hispanic. Median age at diagnosis was 32 (13 - 66) years (table 1). Median white blood cell count (WBC) at presentation was 81,000 (1,800 - 526,000) 109/L. Median peripheral blast percentage at presentation was 35% (0% - 91%), with 23% (7/31) having no peripheral blasts. Median bone marrow blast percentage at diagnosis was 68% (0% - 97%), with 30% (9/30) having <20% blasts. Extramedullary disease was present in 76% (22/29) at diagnosis, with 59% (17/29) presenting with bulky mediastinal disease and 3% (1/31) with central-nervous-system (CNS) disease. Early T-cell precursor phenotype was noted in 16% (5/31) and complex cytogenetics in 18% (5/28). The most common regimen was the pediatric-inspired USC-ALL regimen (based on CCG-1882), 68% (21/31), and the next most common was hyper-CVAD regimen, 23% (7/31). Two patients received alternative regimens and one patient did not receive therapy. 90% achieved CR using the definition of bone marrow blasts <5% and resolution of extramedullary disease. Seven patients (23%) relapsed after achieving CR. Median follow-up for our cohort was 26.5 months, with 71% followed at 1-year, and 58% followed at 2-years. At the time of the study, 17 patients (55%) were known to be alive, and 8 patients (26%) were deceased. Hematopoietic stem cell transplantation (HSCT) was performed in 48% (15/31). The OS was 76% at 1-year and 66% at 5-years. Conclusions According to MD Anderson group, a CR rate of 91% and 5-year OS rate of 67% were reported with hyper-CVAD in T-ALL/LBL patients. Similar results were reported with Berlin-Frankfurt-Munster and the UK ALL XII/ECOG 2993 protocols. Our data reflects a comparable outcome in this predominantly Hispanic adult T-ALL population. Increased utilization of allogeneic HSCT might have been attributed to improvement in survival. Currently, very limited data is available exploring diverse racial and ethnic groups in this disease and we hope our cohort is an addition to the process of better understanding the social and phenotypic differences in T-ALL characteristics and outcomes. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Peripheral blasts are associated with responses to ruxolitinib and outcomes in patients with chronic-phase myelofibrosis.

BackgroundThe presence of peripheral blasts (PB) is a negative prognostic factor in patients with primary and secondary myelofibrosis (MF) and PB ≥4% was associated with a particularly unfavorable prognosis. Ruxolitinib (RUX) is the JAK1/2 inhibitor most used for treatment of MF‐related splenomegaly and symptoms. Its role has not been assessed in correlation with PB.MethodsIn 794 chronic‐phase MF patients treated with RUX, we evaluated the impact of baseline percentage of PB on response (spleen and symptoms responses) and outcome (RUX discontinuation‐free, leukemia‐free, and overall survival). Three subgroups were compared: PB‐0 (no PB, 61.3%), PB‐4 (PB 1%‐4%, 33.5%), and PB‐9 (PB 5%‐9%, 5.2%).ResultsAt 3 and 6 months, spleen responses were less frequently achieved by PB‐4 (P = .001) and PB‐9 (P = .004) compared to PB‐0 patients. RUX discontinuation‐free, leukemia‐free, and overall survival were also worse for PB‐4 and PB‐9 patients (P = .001, P = .002, and P < .001, respectively).ConclusionsPersonalized approaches beyond RUX monotherapy may be useful in PB‐4 and particularly in PB‐9 patients.

FLT3 Gene Mutation in Acute Myeloid Leukemia: Correlation with Hematological, Immunophenotypic, and Cytogenetic Characteristics

Introduction In acute myeloid leukemia (AML), FMS-like tyrosine kinase 3-internal tandem duplication (FLT3-ITD) is a common driver mutation associated with high tumor burden and poor prognosis. This mutation is common in normal karyotype AML and such patients have high leukocyte count. The presence of this mutation can be predicted by certain hematological and immunophenotypic characteristics in day-to-day practice. Objective This study was undertaken to assess the strength of association between FLT3 gene mutation and hematological and immunophenotypic characteristics. Materials and Methods Morphological, hematological, immunophenotypic, and cytogenetic characteristics of FLT3 mutations recorded in 424 patients of AML in adults and children between 2016 and 2019 in a tertiary care cancer center in Western India. Blasts were classified according to French-American-British method. Tumor burden was assessed by serum lactate dehydrogenase (LDH) levels, leucocyte count, and peripheral smear blast percentage. Results Out of 424 cases, FLT3-ITD and FLT3-tyrosine kinase domain mutation were found in 72 and 25 AML patients, respectively. Patients with FLT3 mutation had high tumor burden, characterized by high leukocyte count (p &lt; 0.001), peripheral blood (p = 0.01) and bone marrow (p = 0.03) blast percentage, and high serum LDH (mean 777.8 vs. 586; p = 0.10) compared with FLT3-negative patients. They also featured high platelet count (p &lt; 0.001). Morphological, immunophenotypic, and cytogenetic characteristics also have been presented in the study. Conclusion Observations of the study suggest the presence of definitive hematological and immunophenotypic characteristics along with raised serum LDH levels serve as surrogate markers and indicators of FLT3 mutation in AML patients.

Relation between FMS-like tyrosine kinase 3 factor and hematological parameter in acute lymphoblastic leukemia patients by flow cytometry

BACKGROUND: Acute lymphoblastic leukemia (ALL) is a heterogeneous disorder that is caused by the clonal expansion of immature lymphoid cells with a high rate among children more than adults. FMS-like tyrosine kinase 3 (FLT3) is a cellular receptor belongs to the Class III receptor tyrosine kinase family. The main expression of FLT3 on bone marrow (BM) cells especially CD34+ hematopoietic stem cells, early progenitor cells, dendritic progenitor cells, and other cells of organs (brain, placenta, and testis). Activation of FLT3 results in increased cell proliferation, decreased cell apoptosis, and inhibition of differentiation of cells. This study aims to detect the expression of the FLT3 cluster of differentiation antigen 135 (CD135) in childhood B-ALL patients. Moreover, to correlate this expression with hematological parameters include a complete blood count and BM examination findings and clinical parameters. PATIENTS, MATERIALS AND METHODS: This study was conducted on 30 newly diagnosed pediatric ALL patients. Diagnosis of the disease was based on the blood film, BM examination findings, cytochemistry, and flowcytometry of peripheral blood (PB) and/or BM sample, 1 ml of PB and/or BM sample was collected in EDTA tubes for flowcytometry for detection of CD135. RESULTS: This study found that male patients were more than females with a male-to-female ratio (1.14:1) and a median age of 5 years. Most of the patients had a positive expression of the FLT3 receptor and according to NCI risk groups, 60% of patients fall in the standard risk and 40% in the high-risk group. There was a significant correlation between the level of FLT3 (CD135) and age but no significant correlation with hemoglobin, white blood count, platelets, and peripheral or BM blast percentage. CONCLUSION: In this study, the patients with positive FLT3 blast cells (which is a bad prognostic factor) were associated with good prognostic factors. This proves that FLT3 is an independent prognostic factor.

Using Circ-ANAPC7 as a Novel Type of Biomarker in the Monitoring of Acute Myeloid Leukemia

Introduction: Circular RNAs (circRNAs) are a novel class of RNAs which occupy gene expression at the transcriptional or post-transcriptional level, involve in many physiological processes, and participate in many diseases, especially in cancer. Our previous study showed 1 altered circRNA named circ-anaphase promoting complex subunit 7 (ANAPC7) that was upregulated in acute myeloid leukemia (AML). To further clear the expression and clinical significance of circ-ANAPC7, we enlarged the sample size and illuminated the diagnostic and monitoring value of circ-ANAPC7 in AML. Methods: Real-time quantitative reverse transcription-polymerase chain reaction (RT-qPCR) was supposed to confirm the expression of circ-ANAPC7 of AML patients. We assessed the correlation of circ-ANAPC7 and clinical variables using the Spearman correlation test. The receiver operating characteristic (ROC) curve was carried out to evaluate the diagnostic value. Results: Circ-ANAPC7 was first found to be upregulated in AML, and its expression was correlated to white blood cell counts in peripheral blood and blast percentage in bone marrow. ROC curve analysis revealed that circ-ANAPC7 has a significant value of auxiliary AML diagnosis (area under the curve = 0.915, p < 0.001). Furthermore, the expression level of circ-ANAPC7 was changed accompanied with disease condition transformation. Conclusion: Circ-ANAPC7 was upregulated in newly diagnosed and relapsed AML. It may serve as potential biomarkers for AML patient’s diagnosis and monitoring.

The CXCL12/CXCR4 Pathway As a Potential Target of Tipifarnib in Acute Myeloid Leukemia and Myelodysplastic Syndromes

BackgroundCXCL12 is a chemokine that is essential for homing of myeloid cells in the bone marrow (BM). It has been postulated that a CXCL12 receptor present in myeloid cells, CXCR4, signals in part through HRAS, a protein that is uniquely dependent on farnesylation for activity. Tipifarnib is a potent and selective inhibitor of the enzyme farnesyltransferase (FT) that had been shown to provide clinical benefit in acute myeloid leukemia (AML) and myelodysplastic syndromes (MDS); however, no molecular target that could explain the activity of tipifarnib in AML and MDS has been identified. Based on initial observations in T cell lymphoma (Witzig EHA 2017), we investigated a role for CXCL12 and myeloid cell homing in BM as biomarkers of the activity of tipifarnib in AML and MDS studies.MethodsCTEP20 was a phase 2, multicenter, open-label study that investigated the efficacy and safety of tipifarnib in 158 older adults with previously untreated, poor-risk AML. AML301 was a phase 3 (N=457), multicenter, open-label study that evaluated the efficacy and safety of tipifarnib compared with best supportive care (BSC), including hydroxyurea, as first-line therapy in elderly patients with newly diagnosed, de novo, or secondary AML. INT28 was a multicenter phase 2 study that evaluated tipifarnib in 82 pts with poor-risk MDS. Global gene expression data generated using the Affymetrix U133A gene chip from 34 pretreatment BM samples collected from CTEP20 pts (GSE8970) was analyzed with respect to pretreatment hematological parameters and study outcomes. The Kaplan-Meier method was employed to estimate survival and progression free survival (PFS) and the analysis of prognostic variables. Clinical trial information: NCT00027872, NCT00093990, NCT00050154.ResultsNine complete responses (CR) and 13 best responses of progression of disease (PD) were observed in 34 pts with available BM gene expression data in study CTEP20. Pts in the 3rd (upper) tertile of CXCL12 expression experienced 6 CRs and 2 PDs whereas 1 CR and 8 PDs were observed in the 1st (lower) tertile (p=0.015). BM homing of AML blasts correlated with CXCL12 expression: Median percentage of BM blasts (BMB) and peripheral blasts (PB) were, respectively, 45% and 0% in the upper CXCL12 tertile, and 30% and 26.5% in the lower tertile (p<0.001) (Figure, A). Pts with high tumor burden in BM (BMB blasts>40%) and low circulating blasts (PB<1%) (N=5) had high CXCL12 expression in BM (3423 vs 742 counts, P<0.001, N=27) and experienced prolonged clinical benefit, with 5 CRs and a median PFS of 431 days (431 vs 35 days, HR=0.23, P<0.001, N=27) (Figure, B). The effect of BM homing was then investigated in the phase 3 AML301 trial of tipifarnib vs BSC. While the overall study (N=457) failed to identify an increased efficacy of tipifarnib compared with BSC (median survival of 109 vs 107 days, hazards ratio, HR=1.02, ns), median survival approximately doubled in the tipifarnib am compared with BSC in the subset of patients with high BMB (>40%) and low PB (<10%) while no effect was observed in the control arm (201 vs 109 days, HR=0.58, p=0.02, N=82) (Figure, B). Since CXCL12 is also a potent chemotactic factor for normal neutrophils and syndromes of hyperactivation of the CXCL12/CXCR4 pathway present with neutropenia, we investigated whether neutropenia could be a surrogate of tipifarnib activity. In AML301 pts with WBC counts>LLN (no myelosuppression), increasing neutropenia correlated with increasing clinical benefit from tipifarnib that was due in part to a poorer prognosis of BSC in neutropenic pts (113 vs 80 days median OS, HR=0.81, p=0.036, N=109, for pts with baseline neutrophils<1 giga/L). Finally, we tested the effect of neutropenia on the activity of tipifarnib in INT28. Sixty seven of the 82 MDS pts were transfusion dependent (TD) at study entry. Overall conversion to transfusion independence (TI) and response rate (ORR: CR, CRp, PR) were respectively 16% and 7.5% in the TD pts. Pts with >1 giga/L neutrophils at study entry experienced 5% TI and no responses (N=37) while 30% TI, 2 CRs, 2 CRp and 1 PR were observed in the subset of neutropenic pts.ConclusionCXCL12 expression and BM homing constitute potential biomarkers of the activity of tipifarnib in AML and MDS supporting the hypothesis that the CXCL12 pathway is a potential target of FT inhibitors. [Display omitted] DisclosuresGualberto:Kura Oncology: Employment, Equity Ownership, Other: Chief Medical Officer, Patents & Royalties. Scholz:Kura Oncology: Employment, Equity Ownership, Patents & Royalties. Janes:Wellspring Biosciences: Employment. Kessler:Kura Oncology: Employment. Raza:Kura Oncology: Research Funding; Syros Pharmaceuticals: Research Funding; Novartis: Speakers Bureau; Celgene Inc.: Research Funding; Genoptix: Speakers Bureau; Onconova Therapeutics: Research Funding, Speakers Bureau; Janssen R&D: Research Funding.

Personalized prediction of overall survival in patients with AML in non-complete remission undergoing allo-HCT.

Allogenic hematopoietic stem cell transplantation (allo‐HCT) is the standard treatment for acute myeloid leukemia (AML) in non‐complete remission (non‐CR); however, the prognosis is inconsistent. This study aimed to develop and validate nomograms and a web application to predict the overall survival (OS) of patients with non‐CR AML undergoing allo‐HCT (cord blood transplantation [CBT], bone marrow transplantation [BMT], and peripheral blood stem cell transplantation [PBSCT]). Data from 3052 patients were analyzed to construct and validate the prognostic models. The common significant prognostic factors among patients undergoing allo‐HCT were age, performance status, percentage of peripheral blasts, cytogenetic risk, chemotherapy response, and number of transplantations. The conditioning regimen was a significant prognostic factor only in patients undergoing CBT. Compared with cyclophosphamide/total body irradiation, a conditioning regimen of ≥3 drugs, including fludarabine, with CBT exhibited the lowest hazard ratio for mortality (0.384; 95% CI, 0.266–0.554; p < 0.0001). A conditioning regimen of ≥3 drugs with CBT also showed the best leukemia‐free survival among all conditioning regimens. Based on the results of the multivariable analysis, we developed prognostic models showing adequate calibration and discrimination (the c‐indices for CBT, BMT, and PBSCT were 0.648, 0.600, and 0.658, respectively). Our prognostic models can help in assessing individual risks and designing future clinical studies. Furthermore, our study indicates the effectiveness of multi‐drug conditioning regimens in patients undergoing CBT.

Clinical features of 35 Down syndrome patients with transient abnormal myelopoiesis at a single institution

Transient abnormal myelopoiesis (TAM) is a unique clonal myeloproliferation characterized by immature megakaryoblasts that occurs in 5-10% of neonates with Down syndrome (DS). Although TAM regresses spontaneously in most patients, approximately 20% of TAM cases result in early death, and approximately 20% of survivors develop acute megakaryoblastic leukemia (AMKL). We retrospectively reviewed records of 35 DS patients with TAM to determine the correlation between clinical characteristics and blast percentage. Thirteen of the 35 patients were classified as low blast percentage TAM (LBP-TAM), defined as TAM with a peak peripheral blast percentage ≤ 10%. Although no patient with LBP-TAM experienced systemic edema, disseminated intravascular coagulation, or early death, eight patients had elevated direct bilirubin levels (> 2mg/dl) and one developed AMKL. All patients with LBP-TAM had serum markers of liver fibrosis that exceeded the normal limits, and two patients underwent liver biopsy to clarify the etiology of pathological jaundice. Taken together, our results suggest that patients with LBP-TAM may be at risk of liver fibrosis and liver failure, similarly to patients with classical TAM. Although these patients generally have a good prognosis, they should be carefully monitored for potential development of liver disease and leukemia.

Disseminated Intravascular Coagulation at Diagnosis in Acute Myeloblastic Leukaemia

Background: Disseminated Intravascular Coagulation (DIC) is a life threatening complication frequently observed in acute leukemia. Among the morphological varieties of Acute Myeloid Leukaemia (AML), Acute Promyelocytic Leukaemia (APL) is well established to cause DIC. But there have been reports noted that abnormal DIC parameters also commonly observed in the patients with non-APL AML. This study evaluated the DIC parameters & DIC score according to International Society of Thrombosis and Haemostasis (ISTH) in newly diagnosed non-APL AML patients. Materials and Methods: This cross-sectional observational study was conducted in the Department of Haematology, BSMMU, Dhaka, Bangladesh. 48 newly diagnosed non-APL AML patients were enrolled. Platelets count was measured by auto analyzer (Sysmax XT 2000i/Pentra ABX-120DX) as well as checked manually. Prothrombin time, fibrinogen, D-Dimer were measured using STAGO Coagulation analyzer. The ISTH-DIC scoring system was used to calculate DIC score. The statistical analysis was carried out using the Statistical Package for Social Sciences version 24.0 for Windows. Chi-Square test & Fisher exact test was used for categorical variables. Unpaired t-test was used to compare mean between groups. For all statistical tests, p-value less than 0.05 was considered as statistically significant. Results: By analyzing 48 newly diagnosed patients with non-APL AML, found that DIC developed in 14.6% patients at presentation. Among the DIC parameters, PT and D-dimer were significantly higher in patients presented with DIC. Patients with DIC exhibit lower expression of CD117, CD34, HLA-DR and statistically significant association with negative expression of HLA-DR (p-value 0.034). No significant association was found between presence of DIC and age, gender, bleeding at presentation, morphological type, WBC count or peripheral blast percentage. Conclusion: Abnormalities of DIC parameters in common in patients with AML. A significant portion of patients with DIC have no apparent symptom or bleeding. So, routine screening of DIC parameter at presentation is recommended for early diagnosis & effective management of DIC.

A Personalized Clinical-Decision Tool to Improve the Diagnostic Accuracy of Myelodysplastic Syndromes

Background While histo- and cytomorphological examinations are central to the diagnosis of myelodysplastic syndromes (MDS), significant inter-observer variability exists. The diagnosis can be challenging in pancytopenic patients (pts) without evidence of dysplasia and is contingent on observer expertise. We developed and externally validated a geno-clinical model that uses mutational data and peripheral blood counts/clinical variables to distinguish MDS from other myeloid malignancies. Methods Clinical and genomic data, including commercially available next-generation sequencing panels, were obtained for patients (pts) treated at the Cleveland Clinic (CC; 652 pts), Munich Leukemia Laboratory (MLL; 1509 pts), and the University of Pavia in Italy (UP, 536 pts). All patients had carried a diagnosis of MDS, chronic myelomonocytic leukemia (CMML), MDS/myeloproliferative neoplasm overlap (MDS/MPN), myeloproliferative neoplasm (MPN; either polycythemia vera, essential thrombocythemia, or myelofibrosis), clonal cytopenia of undetermined significance (CCUS), or idiopathic cytopenia of undetermined significance (ICUS). All diagnoses were established with bone marrow aspiration and according to World Health Organization 2017 criteria. The training cohort included data from CC and UP and randomly divided into learner (80%) and test (20%) cohorts. The final model was independently validated in the MLL cohort. A machine learning algorithm was used to build the model; multiple extraction algorithms were used to extract genomic/clinical variables on both the cohort and individual levels. Performance was evaluated according to the area under the curve of the receiver operating characteristic (ROC-AUC) and accuracy matrices. Results Among the 2697 pts included from all sites, the median age was 70 years [36 - 86]. Median hemoglobin (Hb) was 10.4g/dl [6.9 - 15.7], median platelet count (PLT) was 132 k/dL [14 - 722], median WBC count was 5.3 k/dL [1.4 - 49.9], median ANC was 2.8 k/dL [0.3 - 27.7], median monocyte count was 0.3 k/dL [0 - 9.9], and median lymphocyte count (ALC) was 1.1 k/dL [0.1 - 5.4], and median peripheral blast percentage 0% [0 - 8]. The most commonly mutated genes in all patients were (list top 5 genes) and among pts with MDS were SF3B1 (27%), TET2 (25%), ASXL1 (19%), SRSF2 (16%), and DNMT3A (11%); among patients with MDS-MPN/CMML, the most commonly mutated genes were MDS-MPN/CMML (TET2 46%, ASXL1 34%, SRSF2 29%, RUNX1 13%, CBL 12%) ; among patients with MPNs, the most commonly mutated genes were (JAK2 64%, ASXL1 27%, TET2 14%, DNMT3A 8%, U2AF1 7%); among patients with CCUS the most commonly mutated genes were (TET2 41%, DNMT3A 27%, ASXL1 19%, SRSF2 17%, ZRSR2 10%). The most important features for model predictions (ranked from the most to the least important) included: number of mutations detected/sample, peripheral blast percentage, AMC, JAK2 status, Hb, basophil count, age, eosinophil count, ALC, WBC, EZH2 mutation status, ANC, mutation status of KRAS and SF3B1, platelets, and gender. The final model achieved an average AUROC of 0.95 (95% CI 0.93-0.96) when applied to the test cohort and 0.93 (95% CI 0.91 - 0.94) when it was applied to the MLL cohort. The model also provides individual-level explanations for predictions, providing top differential diagnoses and individual-level explanations of how features influence a putative diagnosis (Figure 1b). Conclusions We developed and externally validated a highly accurate and interpretable model that can distinguish MDS from other myeloid malignancies using clinical and mutational data from a large international cohort. The model can provide personalized interpretations of its outcome and can aid physicians and hematopathologists in recognizing MDS with high accuracy when encountering pts with pancytopenia and with a suspected diagnosis of MDS. Disclosures Sekeres: Pfizer: Consultancy, Membership on an entity's Board of Directors or advisory committees; Takeda/Millenium: Consultancy, Membership on an entity's Board of Directors or advisory committees; BMS: Consultancy, Membership on an entity's Board of Directors or advisory committees. Mukherjee:Novartis: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Partnership for Health Analytic Research, LLC (PHAR, LLC): Honoraria; Bristol Myers Squib: Honoraria; Celgene: Consultancy, Honoraria, Research Funding; Aplastic Anemia and MDS International Foundation: Honoraria; Celgene/Acceleron: Membership on an entity's Board of Directors or advisory committees; EUSA Pharma: Consultancy. Gerds:Sierra Oncology: Research Funding; Imago Biosciences: Research Funding; Apexx Oncology: Consultancy; Celgene: Consultancy, Research Funding; Incyte Corporation: Consultancy, Research Funding; Roche/Genentech: Research Funding; CTI Biopharma: Consultancy, Research Funding; AstraZeneca/MedImmune: Consultancy; Gilead Sciences: Research Funding; Pfizer: Research Funding. Maciejewski:Alexion, BMS: Speakers Bureau; Novartis, Roche: Consultancy, Honoraria. Nazha:Jazz: Research Funding; Incyte: Speakers Bureau; Novartis: Speakers Bureau; MEI: Other: Data monitoring Committee.

A Personalized Prediction Model for Outcomes after Allogeneic Hematopoietic Cell Transplant in Patients with Myelodysplastic Syndromes.

Allogeneic hematopoietic stem cell transplantation (HCT) remains the only potentially curative option for myelodysplastic syndromes (MDS). Mortality after HCT is high, with deaths related to relapse or transplant-related complications. Thus, identifying patients who may or may not benefit from HCT is clinically important. We identified 1514 patients with MDS enrolled in the Center for International Blood and Marrow Transplant Research Registry and had their peripheral blood samples sequenced for the presence of 129 commonly mutated genes in myeloid malignancies. A random survival forest algorithm was used to build the model, and the accuracy of the proposed model was assessed by concordance index. The median age of the entire cohort was 59 years. The most commonly mutated genes were ASXL1(20%), TP53 (19%), DNMT3A (15%), and TET2 (12%). The algorithm identified the following variables prior to HCT that impacted overall survival: age, TP53 mutations, absolute neutrophils count, cytogenetics per International Prognostic Scoring System-Revised, Karnofsky performance status, conditioning regimen, donor age, WBC count, hemoglobin, diagnosis of therapy-related MDS, peripheral blast percentage, mutations in RAS pathway, JAK2 mutation, number of mutations/sample, ZRSR2, and CUX1 mutations. Different variables impacted the risk of relapse post-transplant. The new model can provide survival probability at different time points that are specific (personalized) for a given patient based on the clinical and mutational variables that are listed above. The outcomes' probability at different time points may aid physicians and patients in their decision regarding HCT.

Current Treatments Do Not Improve the Prognosis of Patients with Atypical CML and Unclassified MDS/MPN. a Joint Report from Fi-LMC, FIM, Gfch and GFM

Background Atypical CML (aCML) is a rare myeloid neoplasm with molecular heterogeneity and overlapping features of MDS and MPN. Distinction from unclassified MDS/MPNu based on WHO criteria remains difficult, and the management of these closely related entities remains ill-codified. Most patients (pts) are managed with cytoreductive agents, but small series have reported responses to hypomethylating agents or tyrosine kinase inhibitors (TKI), notably ruxolitinib. Allogeneic stem cell transplantation (SCT) is considered the only curative option. To instruct clinical trials with novel agents in this rare and heterogeneous population, real-life cohorts must i) provide prognostic factors and molecular characterization able to stratify patients, and ii) benchmark outcomes with current treatment options. Methods The French National observational study of rare MDS/MPNs performed a retrospective analysis of adult patients with MDS/MPN from 35 centers. Cases were centrally reclassified according to the 2016 WHO criteria to exclude CMML, classical MPNs and CNL. All statistical analyses were done without dichotomizing continuous clinical or biological variables. The prognostic influence of treatments was analyzed considering onset of treatment as a time-dependent covariate (Mantel-Byar method). Results The study population included 136 pts (M/F 83/53), with a median age of 72 years. Only 43 (31.6%) met WHO 2016 criteria for aCML while the remaining 93 were classified as MDS/MPNu. At diagnosis, spleen enlargement or other tumor symptoms were present in 36% of pts, while 32% had constitutional symptoms. Mutations in ASXL1, splice genes (U2AF1, SF3B1, SRSF2 or ZRSR2), SETBP1, EZH2, CSF3R, JAK2 and ETNK1 were present in 68.8%, 50.0%, 30.3%, 15.9%, 12.7%, 12.6% and 7.4% of 63 tested cases, respectively. 25 pts had an AML transformation. With a median follow-up of 29.8 months (0.5-276.4) median overall survival (OS) and AML-free survival (AMLFS) were 25.6 and 20.6 months, resp. Median OS was 20.2 versus (vs) 29.7 months in aCML vs MDS/MPNu, resp (log rank test p=0.2) and median AMLFS was 16.6 vs 27.4 months, resp (p=0.09). In univariate analysis, higher WBC (p=0.003) and lower Hb level (p&lt;10-5) predicted significantly shorter OS, while presence of splenomegaly or other tumor symptoms (p=0.08), higher proportion of IMC (p=0.06), lower platelet count (p=0.08) and dyserythropoieisis (p=0.05) tended to shorten OS. Age, gender, presence of constitutional symptoms, bone marrow or peripheral blast percentage or dysmegakaryopoiesis had no significant impact (all p&gt;0.1). Patients with EZH2 mutations had shorter OS (median 9.9 vs 20.6 months in EZH2 wt pts, p=0.03), while other gene mutations had no significant prognostic impact (all p&gt;0.1). All variables with p &lt;0.1 in univariate analyses were included in a multivariate Cox model. After backward selection, only Hb levels (HR= 0.81, p&lt;10-5) and dyserythropoiesis (HR=2.4, p=0.04) retained independent prognostic value. At any time during follow-up, 89 (65.4%) pts received cytoreductive agents (mostly hydroxyurea), while 23 (16.9%) received TKI (ruxolitinib in 12, imatinib in 8, dasatinib in 3 pts) and 18 (13.2%) HMA, resp. Of note, 8/18 pts received HMA at transformation to AML, while all pts received TKIs prior to AML. Finally, 19 pts (14.0%) received an SCT and 35.3% received ≥2 of the above-mentioned types of treatment. Median time to SCT, HMA and TKI were 10.2, 11.9 and 4.7 months, resp. In multivariate Cox models adjusting for baseline Hb level and dyserythropoieisis, neither cytoreduction (p=0.6) nor SCT (p=0.5) were associated with a significant OS improvement. Treatment with HMA was associated with a significantly worse OS (HR=3.0, p=0.001), but this effect was confounded when transformation to AML, as a time-dependent event, was included in the model (HMA: HR= 1.1, p=0.7, AML: HR=5.1, p&lt;10-6). Finally, treatment with TKIs was also associated with significantly worse OS (HR=2.3, p=0.02). This TKI's detrimental effect was confirmed in a model also accounting for baseline WHO, (log-transformed) WBC count, platelet levels and bone marrow blast percentage. Conclusions Anemia and dyserythropoiesis are important prognostic factors in aCML and MDS/MPNu that should be used to stratify pts included in clinical trials. There is currently no standard of care for these overlap syndromes. Treatment with HMAs and TKIs should be restricted to clinical trials. Disclosures Rea: Incyte Biosciences: Honoraria; Pfizer: Honoraria, Membership on an entity's Board of Directors or advisory committees; Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees; BMS: Honoraria. Roy:Incyte Biosciences: Consultancy. Caers:Takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees; Amgen: Honoraria, Membership on an entity's Board of Directors or advisory committees. Nicolini:Incyte Biosciences: Honoraria, Research Funding, Speakers Bureau; Novartis: Research Funding, Speakers Bureau; Sun Pharma Ltd: Consultancy. Legros:Novartis: Honoraria; BMS: Honoraria; Incyte Biosciences: Honoraria, Research Funding; Pfizer: Honoraria, Research Funding.

A Personalized Prediction Model for Outcomes after Allogeneic Hematopoietic Stem Cell Transplant in Patients with Myelodysplastic Syndromes: On Behalf of the CIBMTR Chronic Leukemia Committee

▪BackgroundAllogeneic hematopoietic cell transplantation (HCT) remains the only potentially curative option for myelodysplastic syndromes (MDS). Genetic alterations have an impact on outcomes after HCT in MDS (Lindsley C, et al, NEJM 2017). Given the significant risks of transplant-related mortality and relapse, identifying patients (pts) who may or may not benefit from HCT is clinically important.We explored how the incorporation of genomic / clinical data using machine learning algorithms can create a personalized prediction model that can predict outcomes after HCT in MDS pts.MethodMDS patients enrolled in the Center for International Blood and Marrow Transplant Research (CIBMTR) Registry were considered for inclusion. Pts were excluded only if blasts were >/= 20% or if they had diagnosis of CMML or MDS/MPN overlap. A panel of 127 gene mutations was performed on samples from peripheral blood prior to HCT. OS was measured from the time of transplant to death or last follow up. Relapse was measured from the time of transplant to time of relapse or last follow up. A random survival forest (RSF) algorithm was used to build the model, in which clinical and molecular variables are randomly selected for inclusion in determining survival and relapse probability, thereby avoiding some of the limitations of traditional Cox step-wise regression in accounting for variable interactions. The accuracy of the proposed model was assessed by concordance (c-) index.ResultsA total of 1514 MDS pts included and randomly divided into training (1059 pts) and validation (455 pts) cohorts. The median age of the entire cohort was 59 years (range 0.4 - 77). Donors were 8/8 HLA-matched unrelated donors (n = 862, 57%), HLA-identical siblings (n = 181, 12%), < 8/8 HLA-matched unrelated donors (n = 296, 20%), or umbilical cord blood (n = 174, 11%). Conditioning regimens included: myeloablative (n=789, 52%), reduced-intensity (n=582, 38%), nonmyeloablative (n=130, 9%), and missing data (n=13, 1%). Cytogenetic analysis by IPSS-R criteria: 579 (38%) very good/good, 269 (18%) intermediate, 287 (19%) poor, 125 (8%) very poor, missing 254 (17%). Median number of mutations/sample was 2 (range, 0-15). The most commonly mutated genes were: ASXL1 (20%), TP53 (19%), DNMT3A (15%), TET2 (12%), RUNX1 (11%), SF3B1 (9%), U2AF1 (8%), and SRSF2 (6%).Variable importance analysis (the most important variables that contributed to the outcome) and multiple backward elimination analysis (identifying the least number of variables that can provide the least error rate) identified the following variables prior to HCT that impacted OS: age, TP53 mutation, absolute neutrophils counts (ANC), cytogenetics per IPSS-R, Karnofsky performance status (KPS), conditioning regimen, donor age, WBC, hemoglobin, diagnosis of therapy-related MDS (t-MDS), peripheral blast percentage, mutations in RAS pathway, JAK2 mutation, number of mutations, ZRSR2, and CUX1 mutations. Variables prior to HCT that affected the cause-specific hazard of relapse included: TP53 mutation, conditioning regimen, cytogenetics per IPSS-R, hemoglobin, disease status prior to HCT, receiving hypomethylating agent vs chemotherapy prior to HCT, number of mutations, age, year of transplant, IPSSR, WBC, KPS, mutations in RAS pathway, in-vivo T cell depletion, ANC, peripheral blast percentage, t-MDS, monosomal karyotype status, number or prior treatments, ASXL1 mutation, bone marrow blast percentage, and PPM1D mutation.To ease the translation of this tool into the clinic, a web application was built where clinical and mutational variables can be entered and the survival probability at 6,12, and 24 months will be computed, Figure 1.The model was valid for OS when it was applied to the validation cohort (c-index of the model in the training cohort was .6, and validation cohort .61.Conclusions:We built a personalized prediction model that uses clinical, molecular, and transplant-related data and can predict the probability of survival in MDS pts that are specific for a given pt. The new model identified several clinical and molecular variables that impacted OS and the cause-specific hazard of relapse. The OS probability at different time points may aid physicians and pts in their decision prior to HCT. [Display omitted] DisclosuresNazha:MEI: Consultancy. Majhail:Incyte: Honoraria; Atara: Honoraria; Anthem, Inc.: Consultancy.

Azacitidine Improves Outcome in Patients with MDS and AML with High Risk Cytogenetics - a Single Center Experience

Azacitidine is a novel hypomethylating agent shown to improve leukaemia free survival and overall survival in comparison with other modalities of treatment in MDS and AML patients. There is proven reduction in transfusion requirements by improvement in haematological parameters with continuous azacitidine use. However azacitidine benefit in high risk cytogenetics group is unclear. Recent retrospective study from GESMD and GFM registries showed that Azacitidine improves outcome in higher‐risk MDS patients with chromosome 7 abnormalities. Here we report our experience in high risk cytogenetics group including complex karyotype.Methodology:-We retrospectively reviewed patients with MDS and AML who received Azacitidine at the Heart of England NHS Foundation Trust from April 2012- January 2018. Patient's demographic data, disease characteristics, treatment, outcome and follow up data were obtained and all patients were included irrespective of the number of the cycles.Results57 patients were included in the analysis. Median age of treatment was 73.9 years. Median number of cycles was 6 (range from 1 to 43). There were 68% of MDS patients, 22.8% of AML and 8.8% of CMML2 patients in the cohort .Varying degree of performance stage was noted including ECOG 0,1 and 2 at 40.4%,43.9% and 7.7% respectively. 9 patients had monosomy 7 and 11 patients had complex karyotype (3/>3). 42.1% had high risk cytogenetics.At presentation, median Hb was 9g/dl, Neutrophil count was 0.7x109/l and platelet count was 41x109/l. Median bone marrow blast percentage was10% and median RIPSS score was 6.5. Causes of death were mainly disease progression and sepsis. 42.2% died due to disease progression and 35.1% died due to sepsis.Overall survival was not affected by age, Bone marrow median blast percentage and median neutrophil count, however, survival was affected by presenting peripheral blast percentage, cytogenetic risk group and was statistically significant (P<0.05)Overall, median progression free survival (PFS) was 19monts while median overall survival (OS) was 12 months. There was no statistically significant PFS or OS difference for patients who had varying performance stage.High risk cytogenetics group:Among high risk cytogenetics group, 21% Patients had red cell transfusion independence at 6 months, 28% had an improvement in the neutrophil count to >1x10^9/L at 6 months. 25% patients had doubling of platelet count at 3 months leading to platelet independence and 17.8% maintained platelet transfusion independence. A significant difference was noted in the group of who had high risk cytogenetic versus other cytogenetic risks with PFS of 15 and 29 months respectively, OS of 8 months and 15 months respectively. with high risk cytogenetics still had a PFS advantage with treatment.ConclusionAzacidine therapy has benefited for the patients who had advanced age AML CMML and MDS who has non high risk cytogenetic based on IPSS-R risk categorization. However, the group of patients with high risk cytogenetic considered historically very poor survival had considerable PFS and OS benefitting treatment rather than best supportive care. DisclosuresMurthy:celgene: Consultancy, Other: Travel grant for educational meeting; Abbview: Other: Travel grant for Educational meeting. Kartsios:Bayer: Consultancy, Honoraria, Speakers Bureau; BMS: Consultancy, Honoraria, Speakers Bureau; Daiichi Sankyo: Consultancy, Honoraria, Speakers Bureau; Boehringer Inglelheim: Consultancy, Honoraria, Speakers Bureau. Nikolousis:Celgene: Consultancy, Other: Travel grant for educational meetings.