Sequential Development of JAK2V617F Mutation and BCR-ABL1 Fusion in Individual Patients With Myeloproliferative Neoplasms: A Linear Clonal Evolution or Parallel Clonal Competition?
Concomitant BCR-ABL1 and JAK2V617F in myeloproliferative neoplasms (MPNs) is rare, and its pathogenesis and clinical significance are unclear.
To investigate the clonal relationship between the 2 genomic alterations, as well as the clinicopathologic impact.
Retrospective analysis of MPNs with sequential development of BCR-ABL1 and JAK2V617F.
Of 6 cases, 5 had JAK2V617F-positive MPN diagnosed before acquiring BCR-ABL1 years later, and 1 had BCR-ABL1+ chronic myeloid leukemia before JAK2V617F-positive myelofibrosis completely replaced the BCR-ABL1+ clone 1 year after tyrosine kinase inhibitor therapy. Among the former group, treatment for the initial MPN involved hydroxyurea, ruxolitinib, and/or supportive care, and the latency to the development of JAK2V617F ranged from 4 to 13 years (median of 9 years). Four cases showed retention of JAK2V617F, whereas BCR-ABL1 emerged as the major clone, including 2 that exhibited parallel increases in JAK2V617F and BCR-ABL1 burdens, with both genomic markers exceeding 50%. Three patients received stem cell transplants and demonstrated sustained engraftment, with the genomic markers below detectable levels.
Most MPNs with concomitant JAK2V617F and BCR-ABL1 are actually composite MPNs with a "second hit" residing on a different clone. Rare cases demonstrate a subclone harboring a "double-hit" in a background of a JAK2V617F-positive stem line clone. The probability of a "double-hit" with a BCR-ABL1+ stem line clone is probably reduced by effective tyrosine kinase inhibitor treatment. The treatment often involves combined kinase inhibitors and/or hydroxyurea, but the outcome is unpredictable; hematopoietic stem cell transplantation may be the ultimate therapeutic option for this complicated disease.
Publication Date: 2021-09-11
Journal: Archives of pathology & laboratory medicine
Incidence, characteristics and risk factors of thromboembolic events in East Asian patients with BCR-ABL1 negative myeloproliferative neoplasms.
The vascular complications have been a major cause of morbidity and mortality among all subtypes of BCR-ABL1 negative myeloproliferative neoplasms (MPN), but the ethnicity-specific data was limited. We therefore conducted a multi-center retrospective, longitudinal cohort study to evaluate the incidence, characteristics and risk factors of thromboembolic events of MPN patients. Of 256 patients, 27.3% experienced thromboembolic events, majority of which occurred before or within 12 months of MPN diagnosis. The multivariable Cox proportional analyses identified leukocytosis (HR 2.67, 95% CI 1.36-5.24, q = 0.004) and history of thrombosis (HR 9.68, 95% CI 2.00-46.88, q = 0.005) as the risk factors for thromboembolism. In subgroup analysis of polycythemia vera and hemoglobin concentration (HR 1.97, 95% CI 1.28-3.04, q = 0.002) appeared to be a significant risk factor of thrombosis, along with age and thrombosis history. In essential thrombocythemia, severity of the established IPSET score was closely correlated with the frequency of thromboembolic events. In primary myelofibrosis, history of thrombosis was associated with thrombosis events (HR 13.85, 95% CI 1.2-159.5, q = 0.035). Overall survival was worse in patients who experienced thromboembolic events. Our study highlighted the importance of recognizing high risk patients and implementing personalized intervention.
Publication Date: 2021-09-10
Journal: Scientific reports
[Precision diagnostics and therapy in hematological malignancies].
Precision diagnostics and therapy have been implemented rather early in clinical hematology due to the easy accessibility of blood and bone marrow, allowing not only for consecutive genetic analysis at diagnosis, remission and relapse, but also for culturing these cells and testing new drugs in vitro. One contributing factor has also been the relatively low number of »driver« mutations in hematologic malignancies and that some of them are gain of function mutations that are relatively easy to target by drugs. Examples of this development are ABL1-, JAK2-, and FLT3-inhibitors for the treatment of chronic myeloid leukemia, myeloproliferative neoplasms, and acute myeloid leukemia, respectively. More recently, gene panel sequencing has been introduced in clinical routine to identify genetic alterations with diagnostic, prognostic and predictive impact, and more sensitive techniques to monitor minimal residual disease are emerging. Whole genome and transcriptome sequencing are currently evaluated as the next diagnostic tool. Finally, a large number of targeted therapies are currently under development and/or undergoing clinical trials.
Publication Date: 2021-05-12
Clinical and Molecular Approach to Adult-Onset, Neoplastic Monocytosis.
In this review, we provide a comprehensive and contemporary understanding of malignant monocytosis and provide a framework by which the appropriate diagnosis with malignant monocytosis can be rendered.
Increasing data support the use of molecular data to refine the diagnostic approach to persistent monocytosis. The absence of a TET2, SRSF2, or ASXL1 mutation has ≥ 90% negative predictive value for a diagnosis of CMML. These data may also reliably differentiate chronic myelomonocytic leukemia, the malignancy that is most associated with mature monocytosis, from several other diseases that can be associated with typically a lesser degree of monocytosis. These include acute myelomonocytic leukemia, acute myeloid leukemia with monocytic differentiation, myelodysplastic syndromes, and myeloproliferative neoplasms driven by BCR-ABL1, PDGFRA, PDGFRB, or FGFR1 rearrangements or PCM1-JAK2 fusions among other rarer aberrations. The combination of monocyte partitioning with molecular data in patients with persistent monocytosis may increase the predictive power for the ultimate development of CMM but has not been prospectively validated. Many conditions, both benign and malignant, can be associated with an increase in mature circulating monocytes. After reasonably excluding a secondary or reactive monocytosis, there should be a concern for and investigation of malignant monocytosis, which includes hematopathologic review of blood and marrow tissues, flow cytometric analysis, and cytogenetic and molecular studies to arrive at an appropriate diagnosis.
Publication Date: 2021-04-24
Journal: Current hematologic malignancy reports
Mutation profile in BCR-ABL1-negative myeloproliferative neoplasms: A single-center experience from India.
Recurrent somatic mutations in the JAK2, calreticulin (CALR), and the MPL genes are described as drivers of BCR-ABL1-negative myeloproliferative neoplasms (MPN) that includes polycythemia vera (PV), essential thrombocytosis (ET), primary myelofibrosis (PMF), and MPN unclassified (MPN-U).
We describe the mutation profile and clinical features of MPN cases diagnosed at a tertiary care center. JAK2V617F and MPL (S505/W515) mutations were screened by allele-specific polymerase chain reaction, while CALR exon 9 and JAK2 exon 12 mutations were screened by fragment analysis/Sanger sequencing. Among the 1,570 patients tested for these mutations during the study period, 407 were classified as MPN with a diagnosis of PV, ET, PMF, and MPN-U seen in 30%, 17%, 36%, and 17%, respectively, screened.
Similar to previous reports from Asian countries, the incidence of PMF was the highest among the classic MPN. JAK2V617F mutation was detected in 90% of PV, 38% of ET, 48% of PMF, and 65% of MPN-U. JAK2 exon 12 mutations were seen in 5.7% of PV and 1.4% of PMF. CALR exon 9 mutations were seen in 33% of ET, 33% of PMF, and 12% of MPN-U. MPL mutations were detected in 2.8%, 2.7%, and 2.9% of ET, PMF, and MPN-U, respectively. Fifteen % of PMF, 26% of ET, and 22% of MPN-U were triple negative.
There was a significantly higher incidence of CALR mutation in PMF and ET cases. Our study highlights the challenges in the diagnosis of JAK2-negative PV and the need for harmonization of criteria for the same.
Publication Date: 2021-04-01
Journal: Hematology/oncology and stem cell therapy
Clinical and Molecular Attributes of Patients With BCR/ABL1-negative Myeloproliferative Neoplasms in India: Real-world Data and Challenges.
Classic BCR/ABL1-negative myeloproliferative neoplasms (MPNs) are characterized by clinical and genetic heterogeneity and include 4 distinct constituents. Very little data on clinical presentation and epidemiology of the same is available from the Indian setting.
Patients referred to Hematology-Oncology from January 2018 to August 2020 with suspected MPNs were included in the analysis and prospectively followed-up. All patients were initially screened, and only those meeting the updated World Health Organization 2016 criteria were included in the analysis. Epidemiologic, clinical, and molecular characteristics were documented, and patients were followed-up prospectively.
A total of 233 patients were referred for evaluation of MPN, of which 63 were included in the analysis, including 39 males and 24 females. The median age at diagnosis was 57 years (range, 28-82 years), and 38% patients were younger than 50 years of age. The most common presentations were incidental detection in 35 (55.5%), abdominal symptoms in 13 (20%), fatiguability in 7 (11%), and recent vascular events in 6 (9.5%) patients. Final diagnosis was polycythemia vera in 27, essential thrombocytosis (ET) in 21, prefibrotic myelofibrosis in 9, and myelofibrosis in 6 patients. The frequency of driver mutations in polycythemia vera included JAK2 in 75%; in ET, JAK2 in 33%, CALR in 33%, and MPL in 4%; and in prefibrotic myelofibrosis, JAK2 in 66% and CALR in 33%. Aspirin was used for all patients along with risk-adapted cytoreduction with hydroxyurea. Ruxolitinib was reserved for symptoms refractory to hydroxyurea. After a median follow-up of 15 months (interquartile range, 10-28 months) from diagnosis, disease progression was noted in 4 patients. Two patients died at the end of the follow-up period, including 1 with secondary acute myeloid leukemia post myelofibrosis and one with ET and coexistent oral malignancy. The remaining 61 patients are alive and on regular treatment.
This is one of the first systematic descriptions and prospective follow-up of patients with BCR/ABL-negative MPNs from India. Our study indicates a younger median age of presentation and higher proportion of JAK2-unmutated disease across all subtypes. The primary role of bone marrow morphology and supportive role of somatic mutations in differentiating MPN subtypes is indicated.
This study sets the stage for a collaborative registry for defining epidemiologic data and long-term outcomes with MPN in India.
Publication Date: 2021-03-25
Journal: Clinical lymphoma, myeloma & leukemia
Pathogenesis of cardiovascular events in BCR-ABL1-negative myeloproliferative neoplasms.
Thrombosis, both in arterial and venous territories, is the major complication of myeloproliferative neoplasms and is responsible for a high rate of morbidity and mortality. The currently accepted risk factors are an age over 60 years and a history of thrombosis. However, many complex mechanisms contribute to this increased prothrombotic risk, with involvement of all blood cell types, plasmatic factors, and endothelial cells. Besides, some cardiovascular events may originate from arterial vasospasm that could contribute to thrombotic complications. In this review, we discuss recent results obtained in mouse models in the light of data obtained from clinical studies. We emphasize on actors of thrombosis that are currently not targeted with current therapeutics but could be promising targets, i.e, neutrophil extracellular traps and vascular reactivity.
Publication Date: 2021-03-05
Diagnoses of myeloproliferative disorder is based on molecular marker. Chronic Myeloid Leukemia and Myeloproliferative neoplasms were considered mutually exclusive and co-existence of BCR/ABL1 and JAK2 mutation is a rare phenomenon.
Here, we present two cases of co-existence of BCR-ABL and JAK2V617F positivity. We characterize the course of the disease, mainly the minimal residual disease.
Ours results highlight that JAK2V617F/BCR-ABL double positivity may be a potential marker of resistance in Chronic Myeloid Leukemia and clonal molecular analysis is mandatory to elucidate the mechanism. Moreover, the combination of JAK and TKI inhibitors might be effective and potentially be guided by molecular monitoring of minimal residual disease.
Publication Date: 2021-02-12
Journal: Journal of oncology pharmacy practice : official publication of the International Society of Oncology Pharmacy Practitioners
Novel and combination therapies for polycythemia vera and essential thrombocythemia: the dawn of a new era.
Essential thrombocythemia (ET) and polycythemia vera (PV) belong to the BCR-ABL1-negative myeloproliferative neoplasms and are characterized by the clonal proliferation of hematopoietic stem and progenitor cells. The contribution of aberrant immune regulation within the bone marrow microenvironment to ET and PV pathogenesis as well as the underlying molecular landscape is becoming increasingly understood.
Authors searched PubMed and conference abstracts in August 2020 for preclinical and clinical studies to provide an overview of the immune pathobiology in ET and PV and the rationale for several novel agents. A discussion of recent clinical trials on interferon and ruxolitinib in ET and PV patients is provided followed by an outline of the future challenges in the field particularly for novel therapeutics and an increasingly individualized, molecularly driven approach to treatment selection. Several novel agents are currently being actively evaluated and are reviewed herein as well.
While hydroxyurea remains the first-line treatment for cytoreduction in most high-risk ET and PV patients, the disease-modifying potential of IFN is promising and could make it a preferred option for selected patients. Advances in molecular testing will enable a more individualized approach to prognostication and treatment selection.
Publication Date: 2020-10-21
Journal: Expert review of hematology
Successful Treatment of a Patient with Chronic Myelogenous Leukemia with Concurrent Janus Kinase 2 (JAK2) R795S Mutation and Breakpoint Cluster Region-ABL1 (BCR-ABL1) Fusion: A Case Report and Literature Review.
BACKGROUND Although the V617F mutation in the Janus kinase 2 (JAK2) gene and the breakpoint cluster region-abl1 (BCR-ABL1) oncogene fusion have been considered mutually exclusive in most myeloproliferative neoplasms (MPNs), many recent studies have described patients with both. This report describes a patient with chronic myelogenous leukemia (CML) and the unusual JAK2 R795S mutation and reviews 23 additional patients with JAK2 gene mutations coexisting with myelofibrosis (MF) and CML. CASE REPORT A 50-year-old woman with MF experienced rapid disease progression 3 weeks later, accompanied by severe abdominal pain and a white blood cell count of 257.45×10⁹/l. Karyotype analysis indicated that she was 46, XY, Philadelphia (Ph) (+) and BCR-ABL1 positive. Bone marrow aspiration after 1 cycle of chemotherapy and treatment with dasatinib showed that her marrow was hypercellular, with an increased number of megakaryocytes and 48.5% myeloblasts expressing the myeloid antigens CD33, CD13, CD34, CD117, and CD71. Next-generation sequencing identified a rare JAK2 R795S mutation. She was diagnosed with CML in blast phase, and was successfully treated with allogeneic hematopoietic stem cell transplantation (allo-HSCT). CONCLUSIONS JAK2 gene mutations, including the rare JAK2 R795S mutation, can coexist with BCR-ABL1 in patients with MPNs. The clinical course of MPN in patients with both BCR-ABL1 and JAK2 mutations may be different from that in patients with classical MPNs.
Publication Date: 2020-10-07
Journal: The American journal of case reports
Comparison of outcomes of HCT in blast phase of BCR-ABL1- MPN with de novo AML and with AML following MDS.
Comparative outcomes of allogeneic hematopoietic cell transplantation (HCT) for BCR-ABL1- myeloproliferative neoplasms (MPNs) in blast phase (MPN-BP) vs de novo acute myeloid leukemia (AML), and AML with prior myelodysplastic syndromes (MDSs; post-MDS AML), are unknown. Using the Center for International Blood and Marrow Transplant Research (CIBMTR) database, we compared HCT outcomes in 177 MPN-BP patients with 4749 patients with de novo AML, and 1104 patients with post-MDS AML, using multivariate regression analysis in 2 separate comparisons. In a multivariate Cox model, no difference in overall survival (OS) or relapse was observed in patients with MPN-BP vs de novo AML with active leukemia at HCT. Patients with MPN-BP in remission had inferior OS in comparison with de novo AML in remission (hazard ratio [HR], 1.40 [95% confidence interval [CI], 1.12-1.76]) due to higher relapse rate (HR, 2.18 [95% CI, 1.69-2.80]). MPN-BP patients had inferior OS (HR, 1.19 [95% CI, 1.00-1.43]) and increased relapse (HR, 1.60 [95% CI, 1.31-1.96]) compared with post-MDS AML. Poor-risk cytogenetics were associated with increased relapse in both comparisons. Peripheral blood grafts were associated with decreased relapse in MPN-BP and post-MDS AML (HR, 0.70 [95% CI, 0.57-0.86]). Nonrelapse mortality (NRM) was similar between MPN-BP vs de novo AML, and MPN-BP vs post-MDS AML. Total-body irradiation-based myeloablative conditioning was associated with higher NRM in both comparisons. Survival of MPN-BP after HCT is inferior to de novo AML in remission and post-MDS AML due to increased relapse. Relapse-prevention strategies are required to optimize HCT outcomes in MPN-BP.
Publication Date: 2020-10-03
Journal: Blood advances
BCR-ABL1-Negative Chronic Myeloproliferative Neoplasms and Pulmonary Hypertension: A Prospective Long-Term Follow-up Study of the Impact of Pulmonary Hypertension on Survival.
To assess the prevalence of PHT in patients with BCR-ABL1-negative CMPN and to evaluate impact of PHT on survival during long-term follow-up.
A total of 122 patients with BCR-ABL1-negative CMPN underwent transthoracic echocardiographic (TTE) evaluation at the beginning of study. Patients undergoing PHT on TTE examination were also evaluated by a pulmonologist. Patients were divided into 3 groups. Group A comprised patients with CMPN-related PHT; group B, patients with no PHT; and group C, patients with PHT due to secondary causes. Patients were evaluated again every 3 to 6 months.
PHT was detected in 33 (27%) of 122 patients. Eight (6.5%) had CMPN-related PHT and the remaining 25 (20.5%) had non-CMPN-related PHT. Positivity for JAK2 V617F mutation in the study population was 72.9%. Groups were similar with respect to hematologic parameters and gender. Follow-up times were as follows: median (range) time from diagnosis to TTE and study end were 34 (1-158) months and 107 (16-251) months, respectively, and from TTE to study end was 88 (7-110) months. No significant differences found among the groups in terms of median time from diagnosis to TTE, follow-up, and overall survival.
BCR-ABL1-negative CMPN patients had a lower prevalence of PHT compared to earlier studies. There was no statistically significant difference in median overall survival between patients with or without PHT. This may be because patients with PHT were asymptomatic and PHT was mild. The impact of PHT on survival was negligible.
Publication Date: 2020-09-14
Journal: Clinical lymphoma, myeloma & leukemia
The impact of CYP2D6*4 and GSTP1 Ile105Val polymorphisms on the susceptibility to develop BCR-ABL1 negative myeloproliferative neoplasms.
Inter-individual variations in the genes encoding xenobiotic-metabolizing enzymes have been reported to alter susceptibility to various diseases involving hematological disorders. The purpose of this case-control study was to investigate the relationship between CYP2D6*4 and GSTP1 Ile105Val polymorphisms and the risk of developing BCR-ABL1 negative myeloproliferative neoplasms (MPN). PCR-RFLP was used for genotyping single nucleotide polymorphisms (SNP) in CYP2D6 and GSTP1 in 139 patients with MPN and 126 controls. There was a significantly increased risk for developing BCR-ABL1 negative MPN for the group bearing the CYP2D6*4 variant allele (X
Publication Date: 2020-09-13
Journal: Molecular biology reports
NT157 has antineoplastic effects and inhibits IRS1/2 and STAT3/5 in JAK2
Recent data indicate that IGF1R/IRS signaling is a potential therapeutic target in BCR-ABL1-negative myeloproliferative neoplasms (MPN); in this pathway, IRS2 is involved in the malignant transformation induced by JAK2
Publication Date: 2020-04-17
Journal: Signal transduction and targeted therapy
Neoantigens in Hematologic Malignancies.
T cell cancer neoantigens are created from peptides derived from cancer-specific aberrant proteins, such as mutated and fusion proteins, presented in complex with human leukocyte antigens on the cancer cell surface. Because expression of the aberrant target protein is exclusive to malignant cells, immunotherapy directed against neoantigens should avoid "on-target, off-tumor" toxicity. The efficacy of neoantigen vaccines in melanoma and glioblastoma and of adoptive transfer of neoantigen-specific T cells in epithelial tumors indicates that neoantigens are valid therapeutic targets. Improvements in sequencing technology and innovations in antigen discovery approaches have facilitated the identification of neoantigens. In comparison to many solid tumors, hematologic malignancies have few mutations and thus fewer potential neoantigens. Despite this, neoantigens have been identified in a wide variety of hematologic malignancies. These include mutated nucleophosmin1 and PML-RARA in acute myeloid leukemia, ETV6-RUNX1 fusions and other mutated proteins in acute lymphoblastic leukemia, BCR-ABL1 fusions in chronic myeloid leukemia, driver mutations in myeloproliferative neoplasms, immunoglobulins in lymphomas, and proteins derived from patient-specific mutations in chronic lymphoid leukemias. We will review advances in the field of neoantigen discovery, describe the spectrum of identified neoantigens in hematologic malignancies, and discuss the potential of these neoantigens for clinical translation.
Publication Date: 2020-03-03
Journal: Frontiers in immunology
[MYC gene amplification attributed to double minutes in a patient with atypical chronic myeloid leukemia].
A 61-year-old man was admitted to our hospital with fever and massive leukocytosis. A bone marrow smear revealed an increased density of myeloid cells in various stages of maturation as well as dysplasia in the neutrophils. There was no proliferation of blasts, eosinophils, or basophils. Genomic analysis of the bone marrow cells revealed no detectable abnormalities associated with myeloproliferative neoplasms, including BCR-ABL1. Therefore, the patient was diagnosed with atypical chronic myeloid leukemia (aCML). Chromosomal analysis revealed the presence of 1-17 double minute chromosomes (dmin) in 20 of 20 tumor cells examined. Multiple MYC signals were detected via interphase fluorescence in situ hybridization, indicating MYC gene amplification in the dmins. Three months after the oral administration of hydroxyurea, leukocytosis reoccurred. Therefore, induction therapy followed with umbilical cord blood transplantation was performed. However, MYC signals remained detectable in the bone marrow sample obtained immediately after neutrophil engraftment, indicating the presence of residual tumor cells. To the best of our knowledge, this is the first case report of aCML with dmin gene amplification, suggesting that the dmin MYC amplification exacerbated the patient's disease.
Publication Date: 2019-12-17
Journal: [Rinsho ketsueki] The Japanese journal of clinical hematology
Risk of disease transformation and second primary solid tumors in patients with myeloproliferative neoplasms.
This study aimed to elucidate patterns of disease transformation to secondary myelofibrosis (SMF) or secondary acute myeloid leukemia (SAML) and the development of second primary malignancies in South Korean patients with BCR-ABL1-negative myeloproliferative neoplasms (MPNs). By using nationwide public health care insurance claims data, we identified and analyzed 7454 patients with MPNs who were newly diagnosed with essential thrombocythemia (ET), polycythemia vera (PV), or primary myelofibrosis (PMF) from 2008 to 2016 and used the data to appropriately trace the disease course. Transformation to SMF or SAML was rare in patients with ET and PV, but patients with PMF had an 8-year cumulative incidence of SAML of 21.4%. Patients with PV or ET had an 8-year cumulative incidence of second primary solid tumors of ∼14%. Patients with MPNs had a 2 times higher risk of developing second primary solid tumors than that of the general South Korean population. Compared with patients with PMF, patients with SMF had a similar overall survival with a lower risk of developing SAML. The use of ruxolitinib did not increase the risk of developing B-cell lymphoma over a median follow-up period of 16.2 months. Disease transformation to SMF or SAML was rare in patients with ET or PV, but SAML was common in patients with PMF. South Korean patients with MPNs had a significantly higher risk of developing second primary solid tumors than that of the general population, particularly for kidney, prostate, brain, liver, and lung cancers.
Publication Date: 2019-11-26
Journal: Blood advances
Clinical and molecular profile of a Brazilian cohort of patients with classical BCR-ABL1-negative myeloproliferative neoplasms.
The classical BCR-ABL1-negative myeloproliferative neoplasms (MPNs) are Polycythemia Vera (PV), Essential Thrombocythemia (ET) and Primary Myelofibrosis (PMF). In developing countries, there are few reports that truly reveal the clinical setting of these patients. Therefore, we aimed to characterize a single center MPN population with a special focus on the correct diagnosis based on the recent review of the WHO criteria for the diagnosis of myeloid neoplasms.
This retrospective study analyzed data from medical records of patients with classical BCR-ABL1-negative MPNs diagnosed from January 1997 to October 2017 and followed at the University Hospital of Ribeirão Preto Medical School.
A total of 162 patients were assessed, 61 with PV, 50 with ET, and 51 with PMF. The mutational status analysis revealed that 113 (69.3%) harbored the JAK2V617F mutation, 23 (14.1%), the CALR mutation, and 12 (7.4%) had a triple-negative status. None of the patients were found to have mutations on the thrombopoietin receptor gene (MPL), including some ET and PMF patients who were not tested. Among the PV patients, 57 (93.5%) were positive for the JAK2V617F mutation, one (1.6%) presented an in-frame deletion JAK2 exon 12 mutation and one (1.6%) presented a missense JAK2 exon 9 mutation, not previously described. The overall survival was lower in the triple-negative patients with PMF, when compared to the JAK2V617F or CALR-mutated (p = 0.002).
The frequency of somatic mutations and survival in our cohort, stratified according to the respective disease, was consistent with the literature data, despite some limitations. Further prospective epidemiological studies of MPN cohorts are encouraged in developing countries.
Publication Date: 2019-11-05
Journal: Hematology, transfusion and cell therapy
Management of advanced phase myeloproliferative neoplasms.
The BCR-ABL1-negative myeloproliferative neoplasms (MPNs), including polycythemia vera, essential thrombocythemia, and primary myelofibrosis, can evolve into a form of secondary acute myeloid leukemia termed MPN in blast phase (MPN-BP). MPN in accelerated phase (MPN-AP), which is defined by 10% to 19% myeloid blasts in the peripheral blood or bone marrow, is a precursor to MPN-BP. Alternative definitions of MPN-AP exist based on studies identifying clinical variables that portend a poor prognosis and high risk for progression to MPN-BP. Allogeneic hematopoietic stem cell transplant remains the only curative therapeutic option; however, advanced age and high comorbidity index preclude the majority of patients from receiving this treatment modality. This article reviews management considerations for the advanced-phase MPNs (MPN-AP and MPN-BP), with a special focus on MPN-AP, and highlights novel experimental therapies.
Publication Date: 2019-08-27
Journal: Clinical advances in hematology & oncology : H&O