WHO Classification Of Myeloid Neoplasms Research Articles

Acute myelomonoblastic leukemia in children, the particularities of extramedullary infiltration based on a clinical case

Childhood acute myeloidleukemia (AML) represents approximately 5% of childhood malignancies and 15% to 25% of pediatric acute leukemia. The extramedullary manifestation of infiltrating clonal blast populations in a variety of organs and tissues in acute myeloid leukemia (AML) is defined as a distinct entity in the 2016 WHO classification of myeloid neoplasms, myeloid sarcoma The rate of complete remission after induction chemotherapy was lower in patients with extramedullary infiltration, overall survival and event-free survival were not different between patients with and without extramedullary infiltration. Purpose of the study: Presentation of a clinical case of ALM type M4 with the presence of an extramedullary infiltrate in the tissue of the central nervous system in children. Materials and methods: The clinical, paraclinical, imaging data of the patient were studied in parallel with the specialized literature on similar cases. Results: Boy, 5 years old, goes to the doctor with accusations of bilateral palpebral edema, bilateral temporal region edema and bilateral exophthalmos , more pronounced on the left. In the general analysis of the blood: - Hemoglobin - 89 g/l , Leukocytes - 7.2 x 10^9/l; unsegmented neutrophil - 1%; segmented - 18%; lymphocytes - 44%; monocytes - 20%; blast cells - 16%; Platelets - 70 x 10^9/l;VSH - 44 mm/h. During the physical examination: the peripheral lymph nodes are palpable. No signs of central nervous system damage. It is supposed the diagnosis: Acute myeloid leukemia, sarcoma, or neuroblastoma. A medullary puncture: moderately cellular marrow was determined, with blastcells 15.2%. Morphologically, it is more similar to acute myelo-monoblastic leukemia FAB-M4. Computerized Tomography-multiple, hyperdense pathological foci, with localization with inand bilateral extraorbital, associated with exophthalmos. The formation from the sphenoid sinus extends to the nasopharynx , through the pterygopalatine fossa, with narrowing of the lumen and mass effect on the palatine tonsils. Immunophenotyping: CD45-/+ SS low 8% population, CD36+ 6%CD64+ monoblasts 8%, Promonocytes /monocytes – (CD64+/CD14+) 25%.He underwent treatment according to the AML BFM 2004 program with numerous complications, andcranial radiotherapy. At the moment, the child is in morphological remission. Conclusions. The differential diagnosis of hyperdense intracranial masses may include neuroblastoma, meningioma, lymphoma, metastases, or sarcomas. Correct and early diagnosis and initiation of specific treatment are essential to increase the survival rate in cases of acute leukemia in children.

Bone and joint disease – Not always a rheumatological diagnosis

Abstract A 17-year-old female presented with a 7-day history of joint pains involving the bilateral knee, ankle and small joints of the hands and feet symmetrically, associated with bilateral knee joint swelling and early morning stiffness and bilateral red eyes. General examination was normal except for pallor. Musculoskeletal system examination revealed bilateral swollen and tender knee joints with restriction of movement along with tenderness in the bilateral shoulder, elbow, ankle joints and spine from T3 to T7 thoracic vertebral levels. Examination of other systems was normal. Investigations showed anaemia, elevated urea and creatinine. Skeletal survey showed multiple lytic lesions. Positron emission tomography revealed multiple punched-out lytic lesions in skull bones, scapulae, sternum, clavicles, ribs on both sides, vertebrae at multiple levels and in pelvic girdle bones. Few lesions showed mild 18fluorodeoxyglucose (18FDG) uptake, metaphyseal moth-eaten lysis in long bones with mild FDG uptake. Bone marrow biopsy and immunohistochemistry confirmed the diagnosis of acute B-cell lymphoblastic leukaemia. The terminology is according to 2016 revision of WHO classification of myeloid neoplasms and acute leukemia.

Diagnosis and treatment of MPN in real life: exploratory and retrospective chart review including 960 MPN patients diagnosed with ET or MF in Germany

PurposeThe WHO 2016 re-classification of myeloproliferative neoplasms resulted in a separation of essential thrombocythemia (ET) from the pre-fibrotic and fibrotic (overt) phases of primary myelofibrosis (MF). This study reports on a chart review conducted to evaluate the real life approach regarding clinical characteristics, diagnostic assessment, risk stratification and treatment decisions for MPN patients classified as ET or MF after implementation of the WHO 2016 classification.MethodsIn this retrospective chart review, 31 office-based hematologists/oncologists and primary care centers in Germany participated between April 2021 and May 2022. Physicians reported available data obtained from patient charts via paper–pencil based survey (secondary use of data). Patient features were evaluated using descriptive analysis, also including diagnostic assessment, therapeutic strategies and risk stratification.ResultsData of 960 MPN patients diagnosed with essential thrombocythemia (ET) (n = 495) or myelofibrosis (MF) (n = 465) after implementation of the revised 2016 WHO classification of myeloid neoplasms was collected from the patient charts. While they met at least one minor WHO-criteria for primary myelofibrosis, 39.8% of those diagnosed with ET did not have histological BM testing at diagnosis. 63.4% of patients who were classified as having MF, however, did not obtain an early prognostic risk assessment. More than 50% of MF patients showed characteristics consistent with the pre-fibrotic phase, which was emphasized by the frequent use of cytoreductive therapy. Hydroxyurea was the most frequently used cytoreductive medication in 84.7% of ET and 53.1% of MF patients. While both ET and MF cohorts showed cardiovascular risk factors in more than 2/3 of the cases, the use of platelet inhibitors or anticoagulants varied between 56.8% in ET and 38.1% in MF patients.ConclusionsImproved histopathologic diagnostics, dynamic risk stratification including genetic risk factors for cases of suspected ET and MF are recommended for precise risk assessment and therapeutic stratification according to WHO criteria.

Philadelphia Negative MPNs, MDS/MPNs and MDS in the Context of Recent WHO Changes and Inclusion of Molecular Signatures into Prognostic Tools: A Single Centre Experience

Introduction: The fifth edition of WHO classification of myeloid neoplasms has introduced major changes in the defining criteria and grouping of MDS, MDS/MPNs and MPNs. Recently published literature has also cited the importance of new risk-scoring systems by integrating genomic profiling with hematologic and cytogenetic characteristics, in order to improve the prognostic discrimination of patients and represents a valuable tool for clinical decision-making. Aim: To find out the prevalence and molecular spectrum of Philadelphia-negative MPNs, MDS/MPNs and MDS in our subset of patients and henceforth to evaluate the impact on diagnosis, risk stratification and treatment decision-making of patients. Methods: This retrospective observational study included all newly diagnosed patients of non-Philadelphia positive MPNs, MDS, and MPN/MDS, in whom complete baseline diagnostic work-up was available including complete blood counts, bone marrow morphology and biopsy, cytogenetic and molecular studies. Results: The most frequent entities in our cohort of patients were primary myelofibrosis (32.8%), MDS (32.8%) and CMML (16.4%). In PIMF, 50% patients were JAK2- mutated while 30% were triple negative (JAK-, CALR-, MPL-). The commoner epigenetic modifiers among MPNs were ASXL1, TET2 and IDH2. The predominant CMML molecular signatures in our patients were NRAS, U2AF2, SETBP1, ASXL and SH2B3. There was no significant effect of WHO changes and recently introduced molecular scoring models on the diagnosis and risk stratification of all these MPN and MDS/MPN patients However, in MDS and PIMF patients, recent WHO subtyping plus IPSS-M & GIPSS scoring respectively enabled refining of risk groups. Conclusion: Molecular profiling helps in better risk stratification of patients across all groups as well as in making therapeutic decisions. However, in resource constrained settings, it is not always possible to stratify patients on the basis of molecular signatures and hence, scoring models such as DIPSS and IPSS-R holds their ground strongly even today for offering appropriate therapy to patients without compromising on quality care.

Clinical Feature and Effect of Demethylation Therapy in Pediatric Patients with Acute Myeloid Leukemia with Myelodysplasia-Related Changes

Objective:To better understanding of the clinical and biological features of childhood AML-MRC, in this study we retrospectively investigated 70 children with AML-MRC admitted to our hospital and compared with AML-NOS. We also analyzed the effect of demethylation drugs in introduction therapy among these patients. Study design: This retrospective cohort study was conducted at the Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College (IHCAMS). Newly diagnosed AML patients at our hospital between January 2009 and December 2021 with complete data regarding baseline characteristics and treatment outcomes were reevaluated as having AML-NOS or AML-MRC according to the 2016 WHO classification of myeloid neoplasms and acute leukemia, strictly excluding cases of therapy-related myeloid neoplasms and AML with recurrent genetic abnormalities. Patients with acute megakaryocytic leukemia were also excluded. Clinical and laboratory data were searched in electronic medical records. Follow-up information was obtained from electronic records or by contacting family members and was initialized from the day of diagnosis to May 31, 2022, or the day of death. Results: Among the 779 newly diagnosed AML patients in our center, 70 patients met the diagnostic criteria of AML-MRC and 73 patients were AML-NOS. Patients with AML-MRC had lower white blood cell count (9.1 (IQR 3.0~30.0) ×109/L vs.17.6 (IQR 5.9~86.8) ×109/L, p=0.002), lower hemoglobin level (74.5 (IQR 63.5~ 86.0) g/L vs. 80.0 (71.0, 94.0) g/L, p=0.025) and lower bone marrow proliferation level (p=0.001) compared with patients with AML-NOS. More FLT3-ITD positive patients were found in AML-NOS patients than AML-MRC patients (33.8% vs. 7.1%, p<0.001). Among the 70 AML-MRC patients, 41(58.6%) were diagnosed by myelodysplasia-related cytogenetics, 10(14.2%) from MDS history, and 19 (27.1%) from a multilineage dysplasia. Monosomy 7 or deletion 7q(-7/7q-) is the most frequent cytogenetic abnormality (21.6%) followed by complex karyotype (18.8%) in AML-MRC patients. Totally 56 AML-MRC patients and 71 AML-NOS patients accepted chemotherapy in out center. Induction treatment for 69 AML-NOS patients were idarubicin/ cytarabine/ etoposide (IAE) or mitoxantrone/cytarabine/ etoposide (MAE) therapy. For AML-MRC patients, demethylation drugs alone or demethylation drugs combined above regime were also used (15 case) besides IAE/MEA therapy (35 case). Six AML-MRC patients and 2 AML-NOS patients accepted homoharringtonine/cytarabine/ granulocyte colony-stimulating factor (HAG) and 3 patients received hematopoietic stem cell transplantation (HSCT) without induction chemotherapy. Overall complete remission (CR) rate of 1 course were 51.0% in AML-MRC and 68.2% in AML-NOS patients. In IAE/MAE group, higher CR rate were seen in AML-NOS patients (70.3%) than AML-MRC patients (48.4%) p= 0.06). AML-MRC patients treated with demethylation drugs seemed to have higher CR rate than introduced by IAE/MAE (64.2 % vs. 48.3%, p= 0.39). HSCT in CR1 were conducted in 29 AML-MRC patients and 19 AML-NOS patients. Median follow-up periods were 2.17 in AML-MRC group and 2.43 years in AML-NOS. Three-year overall survival (OS) and event-free survival (EFS) were 54.4% (95%CI 42.4%~69.8%) and 75.7% (95%CI 62.8%~91.1%) for AML-MRC, 42.3% (95%CI 30.2%~59.2%) and 45.8% (95%CI 32.8%~63.9%) for AML-NOS patients. Cox analysis revealed that HSCT were associated with higher OS (HR 0.21,95%CI 0.1~0.41, p< 0.001). In AML-MRC patients, 3-year OS in HSCT group were significantly higher than that in non-HSCT group [83.4% (95%CI,69.6%~99.8%) vs. 28.0% (95%CI,14.6%~53.9%), p<0.001]. AML-MRC patients with myelodysplasia-related cytogenetics exhibited lower 3-year OS (41.9% ,95%CI,27.5%~63.8%) compared with MDS history group (64.8% (95%CI,39.3%~100.0%) and multilineage dysplasia (77.1% (95%CI,57.3%~100.0%). complex karyotype (41.9% ,95%CI,27.5%~63.8%) and -7(7q-) (40.0% ,95%CI,21.5%~74.3%) AML-MRC patients had lower 3-year OS than normal karyotype (42.3%, 95%CI,21.8%~82.0%) and the other abnormal karyotype (63.5% ,95%CI,37.3%~100.0%) but without statistical difference. Conclusions: Childhood AML-MRC exhibited a comparable adverse outcome with AML-NOS which can be significantly improved by HSCT therapy. Demethylation may help improve the CR rate of AML-MRC. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Clinicopathologic Characteristic and Natural History of Patients with Non Hereditary, Non Polycythemia Vera (NH/NPV) Persistent Polycythemia

Introduction;Polycythemia Vera (PV), is one of the most common Philadelphia chromosome negative myeloproliferative disorders. The identification of Janus Kinase (JAK) 2 mutations and the publication of 2016 revision of WHO classification of myeloid neoplasms has improved diagnostic accuracy of PV. The lower cut-off values of Hemoglobin (Hb) and hematocrit (Hct) used in WHO diagnostic criteria, however, resulted in increased number of adult patients undergoing further evaluation for PV leading to identification of patients with acquired, idiopathic Persistent polycythemia (PP) who not meet WHO criteria for PV despite extensive work up. The clinicopathologic features, disease course, treatment and outcomes of these patients has not been well characterize. This study seeks to described clinicopathologic and molecular profile of cohort of adult patients with Non Hereditary, Non-Polycythemia Vera (NHNPV) Persistent Polycythemia.Methodology;Patients with PP diagnosed and followed up in Fresno community regional medical center/University of San Francisco (UCSF) Fresno, from January 2010 to December 2020 were reviewed. Patients who didn't meet WHO diagnostic criteria for PV after full evaluation including bone marrow biopsies were included in the study. Those with incomplete evaluation, clearly attributable secondary causes of polycythemia or erythropoietin (EPO) level above institutional laboratory reference range (2-18), were excluded from the study. Patients with polycythemia diagnosed at pediatric age were also excluded. The study was approved by institutional review board of UCSF Fresno.Results;129 subjects with JAK 2 Negative PP were reviewed of which 63 had EPO levels within or below the normal range (2-18).Of 36 patients who met the study inclusion and exclusion criteria, majority were males (70% N= 28) and non-Hispanic (56% N=20) with median age at diagnosis of 48.5 years (range 18-70 years). Half of the patients (N=18) have no identifiable etiology of PP. In patients with associated conditions, the most common is non-oxygen requiring clinical OSA (36%) and tobacco smoking (19.4%). Of note, all these patients have EPO level less than 10 which represents the median value of the local institutional defined normal range for EPO. Four (11%) patients have non-iron overloaded hemochromatosis gene mutation (1 Homozygous H63D HFE gene, 2 heterozygous mutation and one with unspecified mutation type).Average Hb and Hct at diagnosis was (17.26+/- 2.23) and (49.76+/- 6.34) respectively. Mean EPO level 7.05+/-2.75 with less than third of patients 8 (22%) with level less or equal to in 5 units. There is no statistically significance difference between mean diagnostic EPO level between males and females in the study (7.20+/-2.89 vs.6.51+/-2.26) and so is the Hct though males have numerically higher levels.The most common bone marrow morphology includes normocellularity (51.76+/-10.36) with erythroid hyperplasia (25%) or megakaryocyte hyperplasia without dysplasia (17%) and grade 1/3 fibrosis 6/36.Abnormal mutations were identified in 17 patients whose bone marrow biopsies were evaluated with limited or extensive next generation sequencing (NGS). Of those patients with available results, 6 patients (35% out of those with NGS) have identifiable previously well described genetic mutations {FANCA S1311fs*1, HGF R134H, TP53 splice site 97-2A>G, KMT2A (Gain), MLL3 (KMT2C) and AFF4, ASXL1 c.1934dupG/TrpfsX12 (p. Gly646)}.9 patients had variance of unknown significant (VUS) mutations (Table 1) with average of 6.2 mutation per patient. Only 1 VUS (TSC1 K587R) was reported in 2 different patients (#7, #9)Mild Myeloproliferative neoplasia (MPN) associated symptoms was reported in 22% of patient with Intermittent phlebotomy (72% N= 26) and aspirin (75% N=27) was the treatment for majority of patients. One patient died during the follow up period. No patient progressed to other MPN, myelofibrosis or AML during the study period.Conclusion;With improved diagnostic criteria and accuracy of PV, increased number of patients are diagnosed with NHNPV Persistent polycythemia. None of the mutation or VUS identified from extensive evaluation is recurrent in our cohort of patient. Longer follow up is needed to delineate clinical significance and prognosis of these mutation in patients with NHNPV persistent Polycythemia. [Display omitted] DisclosuresAbdulhaq: BMS, Alexion, Oncopeptides, Morphosys, Pfizer, Norvartis: Honoraria; Oncopeptides, Alexion, Amgen: Speakers Bureau; Morphosys, BMS, Amgen: Membership on an entity's Board of Directors or advisory committees.

Excess Mortality in Young Patients with Myeloproliferative Neoplasms

▪Introduction: Myeloproliferative neoplasms (MPNs) - essential thrombocythemia (ET), polycythemia vera (PV), and primary myelofibrosis (PMF) - are associated with significant morbidity and shortened survival, irrespective of age (Srour et al. Br J Hematol. 2016). Despite shortened survival, young MPN patients (pts) are often classified as “low-risk” and managed with aspirin alone, phlebotomy-only (PHL), or observation instead of potentially life-prolonging cytoreductive and/or disease-modifying treatment. Age-biased risk assessment and treatment practices deprive young pts from early intervention and access to clinical trials. Our goal is to highlight the unmet need for identifying and implementing life-prolonging treatment in young MPN pts. Here, we determine and compare the excess mortality from MPNs in young (<60 years) to older pts (≥60 years) in the United States (US).Methods: In this population-based study, demographic (age, sex, race), survival, and cause-of-death data were collected for MPN pts from the US Survey, Epidemiology, and End Results (SEER) registry between 2001-2017; and for the general US population from the Centers for Disease Control and Prevention Wide-ranging OnLine Data for Epidemiologic Research (CDC WONDER) database. SEER reports cancers classified by International Classification of Diseases for Oncology, version 3 (ICD-O-3), which evolved with the WHO classification of myeloid neoplasms in 2001 for ET, PV and PMF. Cause-of-death is reported by ICD-10 codes, which we categorized into cardiovascular (CVE), second cancers (CA), acute leukemia (AL), and others. Excess, or relative mortality was determined by the ratio of observed mortality in MPN pts (Kaplan-Meier estimate) over the expected mortality of the US population matched by age, sex, race, and birth-year (actuarial estimate). A one-sided log-rank test was used. Excess mortality of young compared to older pts was determined from a random-effects model using restricted maximum-likelihood estimator method. All analyses were performed using RStudio software v 1.4.1106.Results: The SEER query identified 40,333 MPN pts (ET: 17,420 (43%), PV: 18,027 (45%), PMF: 4,886 (12%)) diagnosed at a median age of 66 years (ET: 67, PV: 65, PMF: 69) of whom 20,470 (51%) were females (ET: 10,709 (61%), PV: 7,768 (43%), PMF: 1,993 (41%)). The 10-year mortality for ET, PV, and PMF pts <60 was 13%, 18%, and 49% respectively (versus 6% for controls); and ≥60 was 59%, 59%, and 87% respectively (versus 35% for controls) (Figure 1A). Excess all-cause mortality was higher in pts <60 compared to ≥60 with ET (2.75 versus 1.82, p<0.001), PV (3.16 versus 1.92, p<0.001), and PMF (10.6 versus 5.73, p<0.001) (Figure 1B). Excess CVE mortality was higher in PV<60 compared to PV≥60 (3.36 versus 2.55, p=0.036) but not in ET or PMF. Excess CA mortality was higher in PV<60 than PV≥60 (2.36 versus 1.53, p=0.002) but not in ET or PMF. Excess AL mortality was high for all pts, particularly PMF, and was not significantly different in pts <60 compared to ≥60Discussion: Excess or relative mortality emphasizes the burden of MPN-related death with current treatment. In this population-based study, we found excess mortality in young MPN pts (<60), greater than in older pts (≥60). This difference may result from age-biased risk assessment and treatment recommendations that recommend lower intensity therapy for young pts. It may be time to revisit these recommendations since accruing evidence demonstrates long-term safety, efficacy and potential survival benefit of available cytoreductive agents. Certain treatments such as interferon-alpha (IFN) may improve survival in PV (Abu-Zeinah et al. Leukemia. 2021), and a recent randomized clinical trial established superiority of IFN over standard of care PHL in young PV pts (Barbui et al. Lancet Hematol. 2021). These data advocate for early intervention with potentially disease-modifying treatment for all pts regardless of age. These data also call into question age-biased exclusions of many young pts from participation in clinical trials of established or promising drugs.Conclusion: Excess mortality of young MPN pts (<60) is unacceptably high and greater than that of older pts (≥60). Clinical trials testing early intervention with potentially life-prolonging treatments are required. [Display omitted] DisclosuresSilver: Abbvie: Consultancy; PharamEssentia: Consultancy, Speakers Bureau. Scandura: Abbvie: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Constellation: Research Funding; MPN-RF (Foundation): Research Funding; CR&T (Foudation): Research Funding; European Leukemia net: Honoraria, Other: travel fees . Abu-Zeinah: PharmaEssentia: Consultancy.

How to unmask unique vulnerabilities in leukaemia

How to unmask unique vulnerabilities in leukaemia Acute myeloid leukaemia (AML) is a group of haematologic malignancies that have been traditionally difficult to classify and treat. Nucleophosmin (NPM1) mutations are the most frequent genetic alteration (about 30 per cent) in AML and NPM1-mutated AML is a new entity in the WHO classification of myeloid neoplasms. However, mechanisms of leukemogenesis and a specific therapy for this leukaemia are missing. The ContraNPM1AML project aims to unravel the complex network of molecular interactions that take place in this distinct genetic subtype and find their vulnerabilities to identify new targets for therapy. The expected discoveries will lead to novel therapeutic approaches and make clinical trials available to patients.

Complete Responses of Myeloid/Lymphoid Neoplasms with Rearrangement of Pdgfra Presenting As AML/ALL/Myeloid Sarcoma to Imatinib Monotherapy

Background Patients with eosinophilia and FIP1L1-PDGFRA fusion protein accounted for approximately 23% (range, 3%-56%) of hyper-eosinophilias. In the 2008 and 2016 WHO classification of myeloid neoplasms, myeloid/lymphoid neoplasms with rearrangement of PDGFRA have been categorized as a distinct type of hematopoietic disorders. Reported cases mostly exhibit normal or mildly elevated bone marrow blasts at diagnosis and imatinib monotherapy is sufficient to induce rapid and complete hematopoietic responses. Patients with rearrangement of PDGFRA but presenting as AML/ALL or myeloid sarcomas are rare and the efficacy of imatinib monotherapy in these patients remains undefined.Methods Two male patients were diagnosed as myeloid neoplasms with rearrangement of PDGFRA in our hospital in 2016. Patient One (aged 31) was presenting as myeloid sarcoma with a 6.9×3.3cm mass on his chest wall and was treated with chemotherapy plus imatinib. Patient Two (aged 25) was presenting as AML with a bone marrow blasts of 27% and was treated with imatinib monotherapy. A literature review searching for patients with PDGFRA rearrangement but presented as AML/ALL/myeloid sarcoma was performed and efficacy of imatinib monotherapy was explored.Results Both of the cases from our hospital survived. Patient One received two cycles of standard chemotherapy (MA and IA) but failed to reduce the tumor size. Imatinib (400mg/d) was initiated immediately. His tumor shrunk dramatically in one week and he achieved complete molecular remission (CMR) in 4 weeks. Patient Two receiving imatinib monotherapy achieved complete hematopoietic remission (CHR) in 1 month and CMR in 3 months after initiation of imatinib (400mg/d). Both patients remain CHR and CMR till now (8 months and 18 months, respectively). We combined our data with 24 cases found in literature that presented as AML/ALL/myeloid sarcoma at diagnosis. All 26 patients were male, and the median age was 40 years (range, 21 to 46). We further compared outcomes of patients treated with imatinib monotherapy or with chemotherapy/HSCT plus imatinib. Most cases in the latter group were given imatinib after chemotherapy induction due to persistent eosinophilia, unsatisfied regress of tumor mass, continued positivity of PDGFRA fusion gene, or disease relapse. The 3-year probabilities of overall survival (OS) were 87.5% for the monotherapy group and 80% for the plus chemotherapy/HSCT group, which were of no statistical significance (p=0.919). In each group there was one patient died from imatinib resistance caused by a mutation in the fusion gene.Conclusions We reported two rare cases of myeloid neoplasms with rearrangement of PDGFRA but presenting as AML/myeloid sarcoma at diagnosis and showed their excellent responses to imatinib. By pooling data in literature we suggest imatinib monotherapy was comparable to combination of chemotherapy/HSCT and imatinib in overall survival rate. To our knowledge, this is the first study to specifically explore outcomes of various treatments for this disease. The efficacy of imatinib monotherapy emphasized importance of FIP1L1-PDGFRA detection at diagnosis of hematopoietic malignancies with eosinophilias. DisclosuresNo relevant conflicts of interest to declare.

Germline ERBB2 Variants Associate with Myeloproliferative Neoplasms

Background: The myeloproliferative neoplasms (MPN) and myelodysplastic syndrome (MDS) are usually sporadic diseases, however, familial cases are well-described. Approximately 10% of MPN cases display familial clustering, and there is a 5-7 fold increased risk of developing an MPN among first degree relatives of MPN patients. While familial MDS appears to be less common, identification of multiple predisposition genes has led to the incorporation of this entity into the most recent WHO classification of myeloid neoplasms. Identification of predisposing germline mutations in the myeloid malignancies has led to a better understanding of the pathophysiology of these diseases and improved clinical care. However, many familial MDS and MPN cases exist in which the inherited genetic lesion is unknown. Our recent investigation of a multigenerational family with inherited MDS/AML marked by erythroid hyperplasia identified a missense variant in ERBB3 that co-segregated with the disease phenotype (1). In this study, we investigated a kindred with an autosomal dominant familial cancer syndrome characterized by both MPN and solid tumor malignancies.Methods: Whole exome sequencing was performed via the Baylor-Hopkins Center for Mendelian Genomics at Center for Inherited Disease Research at Johns Hopkins University. Saliva or peripheral blood samples were used as source DNA. Sequence analysis and variant calling/filtering was performed as previously described (1). Targeted sequencing of the ERBB genes was performed via MiSeq using an Illumina TruSeq Custom Amplicon (v1.5) designed to sequence the entire open reading frame of selected genes. Analysis was performed using Illumina BaseSpace TruSeq applications. Germline variants were identified via variant allele frequency and heterozygous, nonsynonymous variants with a minor allele frequency < 0.01 and a depth > 40x were prioritized.Results: The proband was diagnosed with a JAK2 V617F positive MPN at age 37. Subsequent personal cancer history included melanoma and renal carcinoma. Family history was significant for ovarian cancer and melanoma in her mother, MPN and melanoma in her maternal aunt, and bladder cancer in her maternal uncle (Figure 1A). Exome sequencing of the three family members affected with melanoma was performed in order to identify the predisposing inherited variant in this family. Sequence analysis produced 71 candidate rare, heterozygous, nonsynonymous single nucleotide variants (SNV), including one in the gene ERBB2 . Genotyping of 2 additional family members for the ERBB2 c.3182T>C;p.L1061P SNV established that it co-segregates with disease (Figure 1A). To further investigate the prevalence of rare germline ERBB2 and ERBB3 variants in both MPN and MDS, we performed targeted sequencing of these genes in two discovery cohorts: 1) 96 cases of MPN, of which 63 had a 1st or 2nd degree relative with a family history of MPN and 2) 19 cases of erythroid MDS/AML. Five out of 96 (5.2%) cases of MPN were found to have ERBB2 variants, while 3 of 96 (3.1%) had ERBB3 variants. Of the 19 erythroid MDS/AML cases, no ERBB2 variants were identified, while 1 had an ERBB3 variant. Further, one MPN case with a germline ERBB2 c.G3250T:p.D1084Y variant had a family history of breast cancer in her mother, who also carried this variant (Figure 1B). We analyzed a validation cohort of 630 cases of hematologic malignancies (approximately 20% MPN) sequenced as part of their clinical evaluation at the Sidney Kimmel Cancer Center. Similar to the findings in our discovery cohorts, rare germline ERBB2 variants were enriched in MPN, found in approximately 5% of MPN compared to only 1.8% of all other myeloid disorder diagnoses. In contrast, germline ERBB3 variants were present in 1.6% of MPN compared to 1.8% of the other myeloid disorders (Table).Conclusions: We have identified germline ERBB2 variants that co-segregate with disease in two kindreds with familial cancer syndromes manifesting as a mixed MPN and solid tumor phenotype. In addition, we show that germline ERBB2 and ERBB3 variants are present in patients with hematologic malignancies at a higher incidence than expected in the general population, and ERBB2 variants are associated with an MPN phenotype. Together, these data implicate these genes in the predisposition to myeloid malignancy as well as other familial cancer syndromes. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

CSF3R Mutation in Acute Leukemia and MDS Patients

Introduction: CSF3R somatic mutations has been included in the 2016 revision of the WHO classification of myeloid neoplasms and acute leukemia as a specific molecular diagnostic marker of CNL. Besides CNL, CSF3R somatic mutation have been reported in about 30% of Severe Congenital Neutropenia (SCN) and in a low frequency of other myeloid malignancies (about 4% of CMML, 1.7% of adult AML, 1.9% of children AML), but not in MDS, JMML and ET (Lavallée Et al., Blood 2016; Sano H et al., Br J Haematol 2015). Lavallée et al. reported for the first time that CSF3R mutation are associated with AML with biallelic mutated CEBPA (4/14, 29%) (Lavallée et al., Blood 2016).We aimed to assess the frequency of CSF3R mutation in MDS, AML and ALL patients and the association with other genetic abnormalities.Methods: A retrospective analysis of 974 patients with hematological malignancies, including 297 cases of de novo AML, 144 cases of relapsed AML, 268 cases of de novo ALL, 191 cases of relapsed ALL and 74 cases of MDS patients. 58 genes which common mutated in hematological malignancies were tested by amplicon-based NGS with IonTorrent platform (PGM, Life Technology) and the average sequencing depth was 1000x. 36 leukemia related fusion genes were screened by RT-PCR.Results: We identified CSF3R mutation in 19 patients, which was found in 3.0% (9/297) of de novo AML, 5.6% (8/144) of relapsed AML, 0.5% (1/191) of relapsed ALL and 1.4% (1/74) of MDS. No CSF3R mutation was detected in de novo ALL. All 19 cases had no history of MPN, MDS/MPN or SCN. A total of 8 mutations of CSF3R were detected in 19 patients, 11 cases with T618I mutation, 3 cases with T615A mutation, 1 case with Y779H, Q781*, P809Hfs*8, S810Qfs*6, S813Lfs*2 and D837* mutation respectively, among which 1 patient accompanied with CSF3R T618I and Y779H mutation.In AML cohort, a total of 17 cases with mutant CSF3R, the median age was 20 years (rang, 6-49) and the frequency of CSF3R mutation have no difference between children and adult. Cytomorphology revealed AML M2 (n=11), AML M4 (n=3), AML M5 (n=1), and 1 case have no data available. The median of CSF3R variant allele frequency (VAF) was 25% (3%-49%), 3 cases with VAF <10%, 10 cases with VAF comparable to the concomitant gene mutation with highest VAF. CSF3R mutation was more common as the predominant clone in relapsed AML (87.5% VS 33.3%, P=0.05). The median of concomitant gene mutations was 2 (range 0-3), double-mutated CEBPA (CEBPAdm) was the most frequently concomitant partner of CSF3R mutation (7/17, 41.2% VS 51/382, 13.4%, P <0.05). We also identified 9 cases with AML1-ETO fusion gene which were mutually exclusive with CEBPAdm. In totally, 16 cases of 17 (94.1%) CSF3R mutated AML patient concomitant with core-binding factor gene abnormalities (Fig.1).CSF3R mutation have not been reported in ALL, we identified CSF3R mutation in one patient with B-ALL who was 10 years old and relapsed at 43 months after diagnosed. Bone marrow morphology and immunophenotyping at relapse shows no abnormal neutrophils and myeloid lineage expression were found. No fusion genes were detected. CSF3R T618I and ASXL1 Q803* mutations were detected with VAF of 50% and 51%, respectively, which were confirmed of somatic mutation rather than germline origin. As lack of genetic data at diagnosis, we could not analyze the order of mutation acquisition and clone evolution comprehensively. At the time of reporting, the patients have received allo-HSCT for 4 months and acquired sustained remission. We also detected 1 case of MDS patients (MDS-U) carried U2AF1 S34F, CSF3R Q781* and CBL G413S mutations with VAF of 45%, 32% and 31%, respectively.Due to the limited number of CSF3R mutated cases, we did not perform survival analysis in this study.Conclusion: (1) CSF3R mutation was found in 3.9% of total AML and 3% of de novo AML cohort, rarely seen in MDS and ALL. (2) In AML, CSF3R mutation are prevalent in M2 and M4, and all concomitant with core-binding factor gene abnormalities (CEBPAdm and AML1-ETO fusion gene) and NPM1 mutation which were associated with favorable-risk prognosis. (3) The CSF3R mutation could appeared as predominant clone or subclone in AML and seemly more common as the predominant clone in relapsed AML. As CSF3R mutation also have implications for therapeutic that JAK inhibitors may be efficacious in treating CSF3R-mutant CNL. The implications of prognostic and target therapy (eg. JAK inhibitors) of CSF3R mutation in AML warranting further investigation. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

The Emerging Role of Hematopathologists and Molecular Pathologists in Detection, Monitoring, and Management of Myeloid Neoplasms with Germline Predisposition.

Awareness, widespread availability, and routine use of sequencing techniques in work-up of myelodysplastic syndromes and acute myeloid leukemia have facilitated increased recognition of these entities arising in a background of germline predisposition disorders (GPD). The latest revisions to the WHO classification of myeloid neoplasms incorporate "myeloid neoplasms with germline predisposition" as a separate entity due to the therapeutic implications of this diagnosis. It has become apparent that some of these entities have unique recognizable morphologic findings that can be challenging to interpret at time. Hence, much needs to be studied, posing a new layer of complexity to hematopathologists and oncologists. A thorough understanding of cytogenetic and molecular findings during disease evolution is essential. Consequently, hematopathologists and molecular pathologists play an increasing role in recognition of bone marrow morphologic features that help in recognition of underlying GPD, monitoring, and prompt identification of progression.

Clinicohematological study of spectrum of myeloproliferative neoplasms in a tertiary care hospital

Myeloproliferative neoplasms (MPNs) are a group of disorders of hematopoietic stem cells which were initially recognised by William Dameshek in 1951. Objectives of the study were to diagnose and classify cases of myeloproliferative neoplasms according to 2016 revision of WHO classification of myeloid neoplasms and acute leukaemias, to study various haematological parameters of cases of MPNs (Peripheral smear findings, bone marrow aspirate and trephine biopsy) and their clinical manifestations, to record the cytogenetic/molecular genetic abnormalities of the cases and to categorise CML patients according to Hasford Risk Score as a predictor of prognosis. This study was a prospective study carried out in the Department of Pathology of a tertiary care hospital over two years from June 2016 to September 2018. The study included a total of 41 cases of MPNs. The cases of CMLs were diagnosed on peripheral blood findings, Bone marrow aspiration, Trephine biopsy Serum LDH and uric acid. CML was the most common MPN encountered (37/41; 90.24%) in the present study. Maximum serum LDH elevation was observed in CML cases with a mean value of 1396.6 U/L. Of the 37 CML cases, as per Hasford score, 17 cases were categorised into a low-risk group, 17 cases into an intermediate-risk group and 3 cases into a high-risk group. In the present study of Hasford score in CML cases, it was found that it helps in making a better-informed decision about the adaption of alternative high-risk treatment, and was of value in oncology practice.

A Novel Automated Image Analysis System Using Deep Convolutional Neural Networks to Diagnose MDS

Detection of dysmorphic cells in peripheral blood (PB) smears is essential for diagnosis of hematological malignancies. Myelodysplastic syndromes (MDS) are heterogeneous hematopoietic stem cell disorders that can lead to acute leukemia. Although examinations of bone marrow aspiration and biopsy as well as chromosomal and genetic tests are essential to diagnose these disorders, conventional tests such as complete blood count (CBC) and peripheral blood (PB) smear examinations remain to be initial diagnostic work ups. Detection of dysplastic cells in PB smears and evaluation of CBCs are particularly useful for rapid screening. Thanks to the recent advancement of computational and laboratory technologies, routine manual microscopic examinations have been replaced by automated hematology analyzers in many hematology laboratories. However, detection of dysmorphic cells is still challenging. Therefore, more sophisticated image recognition systems need to be developed. In this study, we developed a novel MDS diagnostic system using PB smears. The system consists of a convolutional neural network (CNN)-based image recognition deep learning system (DLS) and an EGB-based decision-making algorithm (XGBoost). All PB smears were prepared at Juntendo University Hospital. The slides were stained with May Grunwald-Giemsa using a fully automated slide-maker. A total of 703,970 digitalized cell images were collected. First, we trained the CNN-based image-recognition system using 695,030 blood cell images taken from 3,261 PB smears of which 1,165 were obtained from patients with hematological disorders. The hematological disorders included MDS (n=94 cases), myeloproliferative neoplasms (n=127), acute myeloid leukemia (n= 38), acute lymphoblastic leukemia (ALL, n=27), malignant lymphoma (n=324), multiple myeloma (n=82) and AA (n=42). Of all images, these 695,030 images were used to train the CNN-based image-recognition system (Fig 1), and rest of the images (n=8,940) were used for validation. The datasets were classified into 17 cell types and 97 abnormal morphological features by two board-certified laboratory technologists and one senior hematopathologist using the morphological criteria of the Clinical and Laboratory Standards Institute (CLSI) H20-A2 guideline and the 2017 WHO classification of myeloid neoplasms and acute leukemia. After accumulating the image patterns using the training datasets, the performance of the DLS was evaluated using the validation datasets that were prepared for testing the DLS. The internal features learnt by the DLS using t-distributed Stochastic Neighbor Embedding (t-SNE)(Fig 2). In this context, our CNN-based image-recognition system exhibited a sensitivity of &gt;93.5% and a specificity of &gt;96.0% when classifying cells in subsets of the validation datasets. We then created an automated MDS diagnostic system by combining the CNN-based image-recognition system with a form of XGBoost. To establish diagnostic algorithm, the training datasets obtained from 75 MDS and 36 Aplastic Anemia (AA) cases were used for learning of the cell image pattern for each disease. The diagnosis of all datasets was validated by independent hematopathologists using clinical information, laboratory, flow cytometric, and genetic data, and bone marrow aspiration and biopsy findings. The accuracy of the system was tested using validation datasets (26 MDS and 11 AA cases). The system differentiated MDS from AA with the sensitivity and specificity of 96.2% and 100%, respectively (AUC 0.990). In conclusion, this is the first CNN-based automated initial diagnostic system for MDS using PB smears, which is applicable to develop new automated image diagnostic systems for various hematological disorders. Currently, we are collecting more data to improve the accuracy. Disclosures Kimura: Sysmex Corporation: Employment. Takehara:Sysmex Corporation: Employment. Uchihashi:Sysmex Corporation: Employment.

Clinical Features, Laboratory Characteristics, and Response to Therapy in Patients with Acute Undifferentiated Leukemia

Introduction: Acute undifferentiated leukemia (AUL), also referred to as ambiguous lineage leukemia, has been recognized as a unique entity by the WHO classification of myeloid neoplasms since 2008, and is considered a rare subtype. It is characterized by lacking expression of markers diagnostic of myeloid or lymphoid lineages, and encompasses the provisional entity of myeloid/natural killer (NK) leukemia, which also expresses CD56 and other immature T-cell markers. Small studies have reported that AUL is associated with a poor prognosis; however, cytogenetic and molecular characterization of this subgroup of patients is lacking, as are the long-term outcomes of induction therapy and stem cell transplantation (SCT). The goal of this study was to assess clinical and laboratory data of patients diagnosed with AUL at our institution, focusing on its unique characteristics and response to initial therapy.Methods: Parameters assessed at diagnosis included: initial blood counts, bone marrow (BM) blast cell percentage by morphology, specific phenotypic characteristics of BM blasts, molecular mutations and translocations, as well as cytogenetic abnormalities. Immunophenotyping of BM cells at diagnosis was performed using eight-color flow cytometry. Multi-parameter Cytognos acute orientation tube (ALOT) and the combination of the following antigens were used: CD34/CD117/CD14/CD56/CD36/CD123/HLA-DR/CD45/CD64/CD11c. Data were acquired with FACSCanto II flow cytometer and analyzed with Infinicyt software. Myeloperoxidase staining by fluorescence-activated cell sorting (FACS) was considered negative if <3% of blast population stained positive. Data on BM response to initial therapy, based on morphology, immunophenotyping and biopsy, as well as the 18-month outcome following the diagnosis of the first patient in this cohort were assessed.Results: One hundred and sixteen cases of acute myeloid leukemia were diagnosed at the Rambam Health Care Campus between 11/2016 and 5/2018; 16 (1.4%) of them were defined as AUL, since they did not qualify for myeloid, B- or T-cell lineage according to the WHO classification. CD56 positivity was demonstrated in 8 (50%) cases, 5 of which were also CD7 positive. Patient median age was 63 years, 56% were men. None of the patients was found positive for either NPM1 or FLT3 mutations. Likewise, no core binding leukemias were diagnosed in this cohort. Sixty six percent (10/15) of the BM samples demonstrated cytogenetic and/or FISH abnormalities, with 26% complex karyotype cases, and 20% chromosome 7 aberrancies. All but two patients were treated with AML-oriented therapies. None of the patients achieved remission with induction therapy regardless of whether it included a chemotherapy backbone (82% of patients) or a hypomethylating agent. Seven patients have undergone allogeneic SCT, 4 of whom are in remission to date. Two of the remaining transplanted patients died of progressive disease and one developed extramedullary relapse 6 months post-transplant. While 8/16 (50%) patients are alive at 18-month follow-up, only 4 of them (25%) are in remission. Notably, all of the latter patients are SCT recipients. Six out of 8 CD56-positive patients have died of progressive disease, and the remaining two have not achieved remission.Conclusions: The present study, while confirming the poor prognosis of AUL patients, also suggests that a certain subset of such individuals could benefit from an allogeneic SCT. The high percentage of complex karyotype abnormalities, the lack of NPM1 mutations, and the expression of T/NK cell immaturity markers could partly account for the established poor outcome. However, since other molecular abnormalities described in the AML mutational landscape may be involved in AUL initiation/progression, extensive molecular sequencing of this patient population is required. A better understanding of the unique characteristics of this leukemia subtype is also crucial for the design of potentially improved treatment strategies for AUL patients. DisclosuresNo relevant conflicts of interest to declare.

Application of Real-Time PCR for the Detection of BCR-ABL1-like Group in Pediatric Acute Lymphoblastic Leukemia Patients

Background. In 2016 WHO classification of myeloid neoplasms and acute leukemias a new provisional entity ‘B-lymphoblastic leukemia/lymphoma, BCR-ABL1-like’ has been introduced. Two current strategies of BCR-ABL1-like ALL detection are based on gene expression profile revealed either by microarray ('BCR-ABL-like') or by NGS / patented TaqMan low-density array (TLDA) ('Ph-like'). Although both techniques and not widely applicable. Aims. To find out whether expression profile based on combined expression data of 5 genes assessed by real-time PCR can be used for the identification of BCR-ABL1-like pediatric ALL patients. Methods. The study was done on initial bone marrow samples of 147 primary pediatric BCP-ALL patients. Positive cohort included 10 BCR-ABL1-positive ALL patients, negative cohort consisted of 59 cases with known structural or numerical aberrations. Among them there were 21 patients with high hyperdiploidy, 1 low hypodploid, 1 near tetraploid and 1 iAMP21 cases, 23 patients with translocation t(12;21)(p13;q22), 5 cases with t(1;19)(q23;p13), 1 case with t(9;11)(p22;q23) and 6 Down syndrome (DS-ALL) patients. The rest 78 cases were called 'B-others' ALL and designated as training cohort. According to the previously published data (R. Harvey et al. ASH 2013 abs #826.) we picked 5 genes (IGJ, SPATS2L, MUC4, CRLF2, CA6) those expressions were estimated by real-time PCR. ΔCt method was applied in relation to ABL1 expression. In case of having expression results similar to BCR-ABL1-positive cases, patients with BCR-ABL1-negative ALL were attributed as BCR-ABL1-like ALL. In 113 patients we evaluated IKZF1 status by MLPA using P335 kit (MRC-Holland). Presence of ABL1, ABL2, CRLF2, IgH, JAK2, PDGFRb/CSFR1 gene rearrangements were done by FISH. Prognostic significance of BCR-ABL-like profile was estimated in 66 ‘B-others’ patients uniformly treated according to the ALL-MB 2008 protocol. Informed consent was obtained in all cases. Results. Hierarchical cluster analysis and principal component analysis showed that 16 examined samples were clustered together with 9 BCR-ABL1-positive ones. Among them there were 3 DS patients, 1 iAMP21, 1 t(12;21) cases and 11 patients from ‘B-other’ group. IKZF1 deletions and high CRLF2 expression were more frequent in BCR-ABL1-like group in comparison to non-BCR-ABL1-like (67% vs 11%, and 40% vs 6%, correspondingly; p<0.001 in both cases). Among 9 BCR-ABL1-like cases which were assessed by FISH, JAK2 rearrangements were found in 2, CRLF2 in 4 (2 cases of CRLF2-IgH and 2 CRLF2-P2RY8). In 3 patients none of the tested gene rearrangements were revealed. We did not detect any tyrosine kinase fusion genes in 64 non-BCR-ABL-like ‘B-other’ patients (p<0.001). BCR-ABL1-like profile was associated with female gender (80% vs. 57% p=0.011), high initial WBC (≥30*10^9/L) (67% vs. 18%, p=0.001), M3 bone marrow status on day 15 of induction remission (27% vs. 4%, p=0.010). BCR-ABL1-like ALL patients more often were stratified to high-risk group (40% vs. 9%, p=0.001). EFS of BCR-ABL1-like patients was remarkably lower in comparison to non-BCR-ABL1-like ‘B-other’ patients enrolled into ALL-MB 2008 protocol (0.28±0.17 vs. 0.93±0.04, p<0.0001) while cumulative incidence of relapse was significantly higher (0.57±0.19 vs. 0.02±0.02, p<0.0001) with median of follow-up period 4.9 years. The worst outcome was noted in case of combination of BCR-ABL1-like profile and IKZF1 deletions (EFS 0.00), while patients with isolated BCR-ABL1-like profile doing much better (EFS 0.67±0.22). Poor EOI flow-MRD response (>0.1%) together with BCR-ABL1-like profile identified a group of patients with dismal outcome (EFS 0.00 vs 0.88±0.11, p<0.001). Overall accuracy of our BCR-ABL1-like profile for relapse prediction in ‘B-other’ group on ALL-MB 2008 protocol was 0.939 (95% CI 0.881-0.997), for risk of unfavorable event 0.909 (95% CI 0.840-0.978). Conclusion. Thus, we showed that described real-time PCR technology based on expression data of 5 genes allowed to detect the BCR-ABL1-like ALL patients with similar clinical characteristics, genetic parameters and treatment outcome to ones revealed by microarray, NGS or TLDA techniques. We believe that detection of BCR-ABL1-like profile by PCR can be used as fast and easy screening method in ‘B-other’ ALL for the further identification of tyrosine kinase fusion genes or other targetable lesions by NGS or FISH within this group only. DisclosuresNo relevant conflicts of interest to declare.

Changes in the World Health Organization 2016 classification of myeloid neoplasms everyone should know.

This review highlights the main changes in the revised 2016 WHO classification of myeloid neoplasms (published in 2017) that impact diagnosis and ultimately impact management of patients with these diseases. The revision was based on data accumulated since the 2008 WHO classification, much of which relate to new molecular genetic information about these neoplasms. This massive recent influx of data concerning the significance of pathogenic mutations has affected all myeloid neoplasm categories. The new information has been incorporated as part of the diagnostic criteria of many diseases and has led to the creation of new provisional entities defined by genetic features. Germline mutations that predispose to myeloid neoplasms are also emerging as important findings that impact disease classification. The growing body of genetic data have not only altered the classification of myeloid neoplasms, but are also impacting patient management. Genetically-defined disease categories have characteristic prognoses and predicted clinical behavior. Some mutations are associated with responsiveness to certain therapies, including those that target relevant oncogenes. The disease categories in the new classification facilitate the application of risk-adapted therapy based on the most recently available data.

Relapse and cytogenetic evolution in myeloid neoplasms.

Based on the current WHO Classification of Myeloid Neoplasms, cytogenetic findings play a central role in the diagnostic classification of the myeloid malignancies. Cytogenetic abnormalities detected at primary diagnosis may change over time. Karyotype changes can be characterized as cytogenetic evolution, cytogenetic regression or a combination of both. While the exact mechanism of cytogenetic evolution is not completely understood, the process of cytogenetic evolution is not random, but follows different, and often disease-specific patterns during progression and relapse of myeloid neoplasms. Important lessons were learned from the cytogenetic evolution pathways observed over the course of chronic myelogenous leukemia (CML), progressing through chronic phase into accelerated phase and blast crisis. Cytogenetic evolution pathways of CML are divided into major and minor route abnormalities. The major route changes include an extra Ph chromosome (+Ph) trisomy 8 (+8) and the occurrence of an i(17q). The six most common minor route abnormalities include -7, -17, +17, +21 and -Y and one structural change, t(3;21). Recently an increased number of CML cases with karyotype abnormalities in Ph-negative cells have been reported in patients treated with imatinib. These abnormalities include trisomy 8, abnormalities of chromosome 7, and chromosome 20. The significance of the Ph-negative karyotype changes in subsequent development of myelodysplastic syndrome (MDS) or acute myeloid leukemia (AML) is unclear. Nevertheless, the occurrence of clonal abnormalities in Ph-negative cells underlines the importance of conventional cytogenetic studies in monitoring of CML patients. In AML, karyotype changes commonly occur between diagnosis and relapse status post chemotherapy. Karyotype evolution seems more common in patients who had unfavorable aberrations at diagnosis as compared to patients with favorable or intermediate abnormalities. Karyotype evolution results in shortened remission duration as compared to cases without cytogenetic change. Recent studies on cytogenetic evolution at relapse after allogeneic hematopoietic cell transplantation (allo-HCT) were similar to the data observed in chemotherapy-treated AML. Serial bone marrow evaluations after allo-HCT offer insights into the dynamics of karyotype evolution, notably, they demonstrated that a detection of karyotype abnormalities is usually followed by a relapse within the next 90 days. As a contrast, karyotype abnormalities were not observed in patients who do not relapse in the next 3 months. CGE at relapse was associated with significantly decreased postrelapse and post-transplantation survival compared with the non-CGE group. Very few data exist regarding a potential association between the dose or certain types of chemotherapy and cytogenetic evolution. Based on the results of a single study conducted recently, no specific chemotherapy regimen emerged to predispose for cytogenetic evolution. Further studies are necessary to evaluate the impact of the altered bone marrow environment and immunosuppression on karyotype stability.

Models of Prognostication in Chronic Myelomonocytic Leukemia.

Within the group of the myelodysplastic/myeloproliferative overlap neoplasms of the adult age, chronic myelomonocytic leukemia (CMML) is characterized by an extremely variable clinical course. This review aims to cover over the years main advancements in the identification of CMML clinical and biological features associated to survival outcomes and the consequent development of prognostic tools for individual patient treatment decision making. According to the last WHO classification of myeloid neoplasms, three subgroups of patients may be recognized on the base of percentage of blasts in marrow and in peripheral blood (CMML-0, CMML-1, and CMML-2), with corresponding decreasing life-expectations. Nonetheless, in each of the subgroups, prominent disparateness of biological characteristics associates to a large heterogeneity of clinical presentation, with very different prognostic implications. Recent findings indicate that the integration of clinical and molecular data appears to provide the most helpful prognostic information. Together with an orderly enlightenment for the increasing conception of specific disease characteristics, this review offers a comprehensive and thoughtful summary of the prognostic models developed over the last three decades for CMML.

Knockdown of miR-128a induces Lin28a expression and reverts myeloid differentiation blockage in acute myeloid leukemia

Lin28A is a highly conserved RNA-binding protein that concurs to control the balance between stemness and differentiation in several tissue lineages. Here, we report the role of miR-128a/Lin28A axis in blocking cell differentiation in acute myeloid leukemia (AML), a genetically heterogeneous disease characterized by abnormally controlled proliferation of myeloid progenitor cells accompanied by partial or total inability to undergo terminal differentiation. First, we found Lin28A underexpressed in blast cells from AML patients and AML cell lines as compared with CD34+ normal precursors. In vitro transfection of Lin28A in NPM1-mutated OCI-AML3 cell line significantly triggered cell-cycle arrest and myeloid differentiation, with increased expression of macrophage associate genes (EGR2, ZFP36 and ANXA1). Furthermore, miR-128a, a negative regulator of Lin28A, was found overexpressed in AML cells compared with normal precursors, especially in acute promyelocytic leukemia (APL) and in ‘AML with maturation’ (according to 2016 WHO classification of myeloid neoplasms and acute leukemia). Its forced overexpression by lentiviral infection in OCI-AML3 downregulated Lin28A with ensuing repression of macrophage-oriented differentiation. Finally, knockdown of miR-128a in OCI-AML3 and in APL/AML leukemic cells (by transfection and lentiviral infection, respectively) induced myeloid cell differentiation and increased expression of Lin28A, EGR2, ZFP36 and ANXA1, reverting myeloid differentiation blockage. In conclusion, our findings revealed a new mechanism for AML differentiation blockage, suggesting new strategies for AML therapy based upon miR-128a inhibition.