Thrombosis in Philadelphia negative classical myeloproliferative neoplasms: a narrative review on epidemiology, risk assessment, and pathophysiologic mechanisms.

Thrombosis is common in cancer patients and is associated with increased morbidity and mortality. Myeloproliferative neoplasms (MPN) are common malignancies in elderly individuals and are known for a high incidence of thrombotic complications. Different risk factors have been identified in studies, and risk models have been developed to identify patients with MPN at higher risk for thrombosis. Several pathophysiological mechanisms help explain the increased likelihood of thrombosis in these patients. Factors, such as leukocyte and platelet activation leading to the formation of leukocyte-platelet aggregates, activation of the coagulation cascade by microparticles, high levels of inflammatory cytokines, and endothelial dysfunction have a crucial role in thrombosis in MPN patients. Recent studies have demonstrated a significant association between the allele burden of specific genetic mutations (mainly JAK2V617F) associated with MPN and the incidence of thrombotic events, thus suggesting a possible role for these mutations in thrombogenesis.

Diagnosis, prevention, and management of bleeding episodes in Philadelphia-negative myeloproliferative neoplasms: recommendations by the Hemostasis Working Party of the German Society of Hematology and Medical Oncology (DGHO) and the Society of Thrombosis and Hemostasis Research (GTH).

Philadelphia-negative myeloproliferative neoplasms (Ph-negative MPN) comprise a heterogeneous group of chronic hematologic malignancies. The quality of life, morbidity, and mortality of patients with MPN are primarily affected by disease-related symptoms, thromboembolic and hemorrhagic complications, and progression to myelofibrosis and acute leukemia. Major bleeding represents a common and important complication in MPN, and the incidence of such bleeding events will become even more relevant in the future due to the increasing disease prevalence and survival of MPN patients. This review discusses the causes, differential diagnoses, prevention, and management of bleeding episodes in patients with MPN, aiming at defining updated standards of care in these often challenging situations.

Prophylaxis and management of venous thromboembolism in patients with myeloproliferative neoplasms: consensus statement of the Haemostasis Working Party of the German Society of Hematology and Oncology (DGHO), the Austrian Society of Hematology and Oncology (ÖGHO) and Society of Thrombosis and Haemostasis Research (GTH e.V.).

Patients with Philadelphia chromosome-negative myeloproliferative neoplasms (MPN) like polycythemia vera and essential thrombocythemia are at increased risk of arterial and venous thrombosis. Strategies of prevention may consist of platelet aggregation inhibitors and/or cytoreductive agents depending on the underlying disease and the individual risk. Clinical evidence for management of acute venous thromboembolic events in MPN patients is limited. Modality and duration of therapeutic anticoagulation after venous thrombosis has to be evaluated critically with special regard to the increased risk for spontaneous bleeding events associated with the underlying diseases. Both for therapy of the acute event and for secondary prophylaxis, low-molecular-weight heparins should preferentially be used. A prolongation of the therapeutic anticoagulation beyond the usual 3 to 6 months can only be recommended in high-risk settings and after careful evaluation of potential risks and benefits for the individual patient. New direct oral anticoagulants (NOAC) should not preferentially be used due to lack of clinical experience in patients with MPN and potential drug interactions (e.g. with JAK inhibitors). Consequent treatment of the underlying myeloproliferative disease and periodical evaluation of the response to therapy is crucial for optimal secondary prophylaxis of thromboembolic events in those patients.

Philadelphia-Negative Myeloproliferative Neoplasms Around the COVID-19 Pandemic.

PURPOSE OF REVIEW: Coronavirus disease 2019 (COVID-19) is associated with a high rate of respiratory failure, thromboembolism, bleeding, and death. Patients with myeloproliferative neoplasms (MPNs) are prone to both thrombosis and bleeding, calling for special care during COVID-19. We reviewed the clinical features of MPN patients with COVID-19, suggesting guidance for treatment. RECENT FINDINGS: One study by the European LeukemiaNet collected 175 MPN patients with COVID-19 during the first wave of the pandemic, from February to May 2020. Patients with primary myelofibrosis (PMF) were at higher risk of mortality (48%) in comparison with essential thrombocythemia (ET) (25%) and polycythemia vera (19%); the risk of death was higher in those patients who abruptly discontinued ruxolitinib. In patients followed at home, in regular wards, or in ICU, the thrombosis rate was 1.0%, 2.8%, and 18.4%, respectively. Independent risk factors for thrombosis were ET phenotype, transfer to ICU, and neutrophil/lymphocyte ratio; major bleeding occurred in 4.3% of patients, particularly those with PMF. MPN patients with non-severe COVID-19 treated at home should continue their primary or secondary antithrombotic prophylaxis with aspirin or oral anticoagulants. In the case of hospitalization, patients assuming aspirin should add low molecular weight heparin (LMWH) at standard doses. In contrast, LMWH at intermediate/therapeutic doses should replace oral anticoagulants prescribed for atrial fibrillation or previous venous thromboembolism. Intermediate/high doses of LMWH can also be considered in ICU patients with ET, particularly in the case of a rapid decline in the number of platelets and progressive respiratory failure.

Accelerated Phase of Atypical Chronic Myeloid Leukemia with Severe Disseminated Intravascular Coagulation at Initial Presentation.

Patients with myelodysplastic syndrome/myeloproliferative neoplasm (MDS/MPN) are often asymptomatic and thus can remain undiagnosed until they become symptomatic due to progression to the accelerated phase (AP) or transformation to acute leukemia (leukemic transformation; LT). We herein report the case of a previously healthy 38-year-old man who had hyperleukocytosis with dysplastic myeloid precursor cells and severe disseminated intravascular coagulation. Hematopoietic recovery with features of atypical chronic myeloid leukemia (aCML) after induction chemotherapy was a diagnostic clue. Although rare, this case highlights the limitation of the diagnostic approach for aCML with AP or LT at the initial presentation.

Correlation between leukocytosis and thrombosis in Philadelphia-negative chronic myeloproliferative neoplasms.

The evidence that leukocytes may contribute to the pathogenesis of thrombosis in Chronic Myeloproliferative Neoplasms is increasing but not definitive. To further enforces whether an increased leukocyte count is associated with thrombosis and whether this effect can be modulated by cytoreductive therapy, we analyzed the clinical course of 187 patients with Polycythemia Vera (PV) and Essential Thrombocythemia (ET) followed at two Italian Institutions over a period of 7 years. The association was measured at diagnosis or before thrombotic events: a multivariable analysis was carried out using data at baseline and time-dependent covariates. We found that white blood cells (WBC) count above 9.5 x 10(9)/L at diagnosis (baseline analysis) was associated with thrombosis during the follow-up (Hazard Ratio [HR] of 1.8, p 0.03). At the time-dependent analysis, therapy with hydroxyurea (HU), lowering by 35% the baseline WBC level, reduced such strength of association giving a HR of 1.3 (p value non significant). We found a trend between WBC level and thrombosis in untreated low-risk patients (RR of 1.9, 95% CI 0.9 to 3.1); in high-risk patients treated with HU this correlation was clearly lost (RR 1.1, 95% CI 0.2 to 2.7). Finally, we could not identify the presence of JAK2 (V617F) as a risk factor for thrombosis. Properly designed prospective studies should corroborate such results.

Rapid detection of CALR type 1 and type 2 mutations using PNA-LNA clamping loop-mediated isothermal amplification on a CD-like microfluidic chip.

Bleeding and thrombosis represent common complications in myeloproliferative neoplasms (MPN) and significantly contribute to morbidity and mortality. Molecular markers, including CALR mutations, were considered not only as diagnostic markers, but also as risk factors for bleeding and thrombosis associated with MPN, especially for patients in remote primary hospitals. We sought to develop an easy-to-use assay for the rapid detection of CALR type 1 (CALR-1) and type 2 (CALR-2) mutations in Philadelphia chromosome-negative MPN patients. Peptide nucleic acid-locked nucleic acid (PNA-LNA) clamping loop-mediated isothermal amplification (LAMP) assays were established, which were integrated into a centrifugal compact disc (CD) microfluidic platform. A total of 158 clinical blood samples were tested simultaneously by this microfluidic platform and an in-house real time PCR assay. The detection performance of the LAMP arrays was validated and conflicting results were identified by Sanger sequencing. The results suggested that the LAMP methods we developed exhibited good sensitivity, specificity, and precision. By real time fluorescence assay the detection limit for CALR-1 and CALR-2 mutations could reach as low as 1% and 0.5% respectively, and 10% and 5% respectively by visual method. There were no nonspecific background amplifications among different detection systems. For the CALR-1 and CALR-2 LAMP detection systems, intra-batch CV values of 1% mutated plasmid were 10.56% and 10.51% respectively, and the inter-batch CV values were 19.55% and 18.39%, respectively. The products were all analyzed by melting curve analysis and electrophoresis followed by Sanger sequencing analysis, which were consistent with the database sequences. The microfluidic platform could complete rapid detection of CALR-1/2 mutations within 60 min. The results of clinical samples detected by our CD-like microfluidic chipLAMP assay and rtPCR assay suggested that 133 samples were CALR wild type, 15 were CALR-1 mutation type, and 9 were CALR-2 mutation type. The correlation coefficient value (Kendall's tau_b) of the two assays was 0.99. Interestingly, by the newly established detection platform, we were surprised to find that one patient of Chinese origin harbored both CALR-1 and CALR-2 mutations. This result was verified by Sanger sequencing analysis. The LAMP detection systems developed herein displayed good sensitivity, specificity, and stability. Additionally, the detection results could be directly judged by color changes of the reaction systems without any auxiliary equipment. Thus, the platform we developed has the potential of being widely used in remote and economically undeveloped areas in the future.

Extensive cytogenetic studies of clonality following interferon-alpha therapy in chronic myeloid leukemia occurring in monosomic cells in a patient with Turner syndrome mosaic.

In a 27-year-old female with Turner syndrome mosaic, Philadelphia (Ph) chromosome-positive chronic myeloid leukemia (CML) occurred only in the monosomic cells (45, Xc). Extensive cytogenetic studies, including triple-color fluorescence in situ hybridization (FISH), revealed that Ph-positive monosomic cells (45, Xc), Ph-negative monosomic cells and normal diploid cells (46, XX) were present in her bone marrow at diagnosis. After successful interferon therapy, the non-leukemia cells expanded and reconstituted normal hematopoiesis resulting in complete cytogenetic response, following the selective suppression of the monosomic Ph-positive leukemia clone. The ratio of Xc to XX cells in bone marrow cells was significantly increased to that in skin fibroblasts. Moreover, the ratio of Ph-positive cells to Ph-negative cells was found to be significantly different between karyotyping and FISH. Studies of this quite unique case not only confirmed the clonality of CML, effectiveness of interferon-alpha and X chromosome imbalance among different tissues, but also demonstrated a discrepant increase of the BCR/ABL-positive clone in CML. The latter supports the hypothesis that reduced programmed cell death may be the primary mechanism responsible for the expansion of the leukemia clone in CML. Our study verifies the importance of extensive analysis of a neoplastic disease in patients with a constitutional chromosomal abnormality.

Transformation from atypical chronic myeloid leukemia to chronic myelomonocytic leukemia as progression of myeloid neoplasm with platelet-derived growth factor ß rearrangement.

Myeloid neoplasms associated with platelet-derived growth factor b (PDGFRB) rearrangement usually keep only one morphologic type unless blast crisis. We describe a unique case of hematological features transformation from atypical chronic myeloid leukemia to chronic myelomonocytic leukemia, and imatinib showed no clinical therapeutic effects. The phenomenon indicates that different types of myeloid neoplasms associated with PDGFRB rearrangement can transform into one another with the progression of the disease, and to some extent, this transformation suggests the aggravation of disease.

Evaluation of Inflammation Parameters in Philadelphia Negative Chronic Myeloproliferative Neoplasia Patients.

BACKGROUND: Chronic myeloproliferative diseases are clonal stem cell diseases which occur as a result of uncontrollable growth and reproduction of hematopoietic stem cells, which are the myeloid series source in bone marrow. Recent studies have suggested that chronic inflammation can be a triggering factor in the clonal change in chronic myeloproliferative neoplasia (CMPN). In our study, we evaluated the existence of a chronic inflammation process in our Philadelphia negative (Ph-)CMPN patients using inflammation parameters in combination with demographic, laboratory and clinical characteristics of the patients. MATERIALS AND METHODS: Demographic characteristics, clinical and laboratorial data, and thrombosis histories of 99 Ph-CMPN patients, who were diagnosed at our outpatient clinic of hematology in accordance with WHO 2008 criteria, were analyzed retrospectively,with 80 healthy individuals of matching gender and age included as controls. Complete blood counts, sedimentation, C reactive protein (CRP), JAK V617F gene mutations, abdomen ultrasound images and previous thrombosis histories of these patients were retrospectively analyzed. RESULTS: Ph-CMPN and healthy control groups included 99 and 80 cases, respectively. PV, ET and MF diagnoses of patients were 43 (%43.4), 44 (44.4%) and 12 (12.1%), respectively. JAK V617F gene mutation was found to be positive in 64 (71.1%) of all cases and in 27(65.8%), 32 (82%), 5 (50%) of the cases in PV, ET and PMF groups, respectively. Thrombosis was determined as 12 (12%) in the entire group, 12.5% in the JAK V617F negative and 15.3% in the positive patients, with no statistical significance (p=0.758). No significant difference was observed between patients with and without previous thrombosis history in respect to hemogram parameters, sedimentation and CRP (p>0.05), neutrophil to lymphocyte ratio (NLR), erythrocyte distribution width (RDW), mean platelet volume (MPV) and sedimentation levels of the patient.

Fatal Haemophilus influenzae septicemia following bronchoscopy in a splenectomized patient.

We describe a 46-year-old splenectomized patient who died of Haemophilus influenzae septicemia 16 h following bronchoscopy. Although rare, postsplenectomy overwhelming sepsis is always a danger in splenectomized patients undergoing invasive procedures. Chemoprophylaxis should be considered in asplenic patients peribronchoscopy.

Atypical Ph negative chronic myeloid leukaemia presenting as sudden profound deafness.

A patient with atypical Ph negative chronic myeloid leukaemia presented with the sudden onset of profound deafness. He survived only eight months. Detailed histological investigation performed at necropsy showed loss of ganglion cells and afferent nerve fibres in the cochlea and vestibule associated with extensive fibrosis and new bone formation in the labyrinthine spaces. Both leucophoresis and high dose chemotherapy capable of rapid cytoreduction are recommended in patients with chronic myeloid leukaemia with profound hearing loss, as conventional chemotherapy is rarely followed by recovery.

Pure red cell aplasia in a case of Ph negative BCR/ABL rearranged CML with t(12;14)(q23;p11).

A patient with chronic myelogenous leukemia (CML) associated with pure red cell aplasia (PRCA) is reported. The occurrence of PRCA has been described previously in sporadic cases of Philadelphia chromosome (Ph) positive CML. In this patient, however, the Ph-chromosome was not detected; cytogenetic analysis revealed a t(12;14)(q23;p11) as the sole abnormality. Molecular studies by Southern and PCR analyses showed the rearrangement of the BCR and ABL sequences and expression of the chimeric bcr/abl mRNA, thus confirming the diagnosis of CML. To our knowledge, this is the first report on a case of PRCA associated with Ph negative CML at diagnosis. The possible connection between CML and PRCA is discussed.

Atrophie blanche in chronic myelogenous leukemia.

Atrophie blanche is a syndrome of painful vasculitic infarctive lesions of the lower extremities that heal leaving characteristic atrophic, porcelain white scars. The syndrome may occur as an idiopathic entity or associated with various hematologic and collagen vascular disorders. We present the first recognized case of atrophie blanche in a patient with chronic myelogenous leukemia. This presentation may be part of the expanding spectrum of nonspecific cutaneous manifestations of leukemia (leukemids).

Spontaneous splenic rupture in atypical (Philadelphia chromosome negative) chronic myeloid leukaemia following blastic crisis.

Philadelphia chromosome negative and bcr/abl negative chronic myeloid leukaemia (CML) is an uncommon atypical CML. We describe a patient with this disorder who experienced an acute blastic transformation that resulted in rapid splenic enlargement and subsequent atraumatic splenic rupture. Clinically, spontaneous splenic rupture may be a difficult diagnosis to make and this case highlights the importance of considering atraumatic splenic rupture as a cause for unexplained abdominal pain in a patient with a haematological malignancy.

[Blast crisis accompanied by severe DIC of Ph negative chronic myeloid leukemia showing t(9;16) and positive M-BCR/ABL rearrangement].

A 66-year-old woman complained of chest discomfort in January 1995. In March the accelerated phase of chronic myeloid leukemia (CML) was diagnosed. Chromosomal analysis demonstrated negative Ph and positive t(9;16) (q34;p11) with positive major BCR/ABL chimeric mRNA. Administration of hydroxycarbamide was initiated, but in May she developed high fever and severe left hypochondralgia. Her WBC was 62,100/microliter (blast 64%), and LDH was 3,590 IU/l. Bone marrow examination showed 78.6% blasts, with a nucleated cell count of 74 x 10(3)/microliter. Blasts were negative for esterase stain and partially positive for both peroxidase stain and PAS reaction. Surface marker analysis revealed that blasts were positive for CD13, CD19, CD33, CD34, and HLA-DR. A diagnosis of blast crisis was made and she was treated with the VDS-CP regimen with heparin for DIC. After temporary improvement her disease recurred rapidly with severe DIC. Treatment with low molecular weight heparin and fresh frozen plasma failed to control DIC and she died of subarachnoid hemorrhage on the 48th hospital day. This is the first veprted of case Ph-negative, M-BCR/ABL-positive CML with t(9;16) accompanied by severe DIC.

[Acute thrombotic complication at the debute of the Philadelphia chromosome-negative myeloproliferative syndrome]. / Akut trombotisk komplikation ved debut af det Philadelphia-kromosom-negative myeloproliferative syndrom.

METHODS: We describe eight patients with a diagnosis of a chronic myeloproliferative disorder, characterised in most patients by severe thrombotic complications at the debut of the disease. RESULTS: The symptoms were life-threatening in seven patients: acute upper gastrointestinal haemorrhage from oesophageal varices in four, an acute abdominal catastrophy owing to mesenteric vein thrombosis with intestinal gangrene in two, and a large cerebral infarction, which was lethal, in one. The same patient also suffered a thrombosis of the axillary and subclavian veins. Neurological symptoms, with headache, visual disturbances, dizziness, and impaired memory, were initial cardinal symptoms. In two patients, explorative laparotomy was performed with intestinal resection owing to gangrene. One patient had a toe amputation. DISCUSSION: The above symptoms are explained by thrombosis in the microcirculation because of thrombocytosis and circulating platelet aggregates. In patients with polycythaemia vera, the elevated haematocrit contributes significantly to the impaired microcirculation. Early diagnosis and management of these disorders are of utmost importance to prevent the potentially life-threatening complications described above.

[Onset of Philadelphia chromosome negative chronic myeloid leukemia with symptoms of intrahepatic cholestasis]. / Intrahepatikus cholostasis tüneteivel kezdödö Philadelphia chromosoma negatív chronikus myeloid leukaemia.

The case of a chronic myelogenous leukemia (CML) starting in an unusual form in a young woman is reported. Rapidly progressing icterus was the first and leading symptom of the disease. Simultaneously with the exclusion of the possibility of hepatitis and extrahepatic obstruction of the bile duct the qualitative blood picture roused the suspicion of a myeloproliferative disease. Detailed hematological examinations confirmed Philadelphia chromosome (Ph1) negative CML. Besides the histologically diffuse leukemic infiltration intrahepatic cholostasis could be demonstrated in the background of the icterus. In the chronic and accelerated phase clinical symptoms developing as a consequence of hepatic organic manifestation were dominating. In the authors's case the moderate leukocytosis, initial thrombocytopenia, absence of splenomegaly, early blast-phase and short survival were atypical, characteristic of Ph1 negative CML. The diagnosis and the absence of other associated hepatopathies was supported also by the post-mortem examination. CML beginning with icteric symptoms due to intrahepatic cholostasis is considered as rarity in the literature.

Chronic kidney disease in patients with the Philadelphia-negative chronic myeloproliferative neoplasms.

BACKGROUND: The progression of kidney function and frequency of chronic kidney disease (CKD) in patients with the Philadelphia-negative myeloproliferative neoplasms (MPN) is unknown, although CKD is linked to increased mortality. METHODS: This longitudinal retrospective study evaluates the estimated glomerular filtration rate (eGFR) in 143 MPN patients over a period of 9 years. RESULTS: 29% of patients had CKD stage 3 or 4 at time of diagnosis. 20% of patients had a rapid annual loss of eGFR (>3mL/min/1.73m(2)) and eGFR was negatively correlated to monocyte and neutrophil counts. CONCLUSION: Kidney impairment might contribute to the increased mortality observed in MPN patients.