Polycythemia Vera-Associated Complications: Pathogenesis, Clinical Manifestations, And Effects On Outcomes

Dermatologic manifestations of hematologic disorders

Distinguishing key morphologic features and understanding the pathophysiology of common cutaneous manifestations of hematologic disorders is essential to ensure prompt and appropriate treatment. In fact, classic cutaneous signs may provide the first clue to the diagnosis of an underlying hematologic disease. Disorders of coagulation, vascular abnormalities, or cutaneous infiltration and deposition are responsible for the underlying pathophysiology of cutaneous manifestations in the majority of cases. Hematologists often feel ill-equipped in identifying morphologic changes in the skin. Thus, the purpose of this review is to provide a comprehensive overview of classic cutaneous manifestations and diagnostic considerations of the associated hematologic conditions. Though there is a specific focus on non-malignant disorders, those straddling the spectrum of malignancy are also discussed. In many disease states, the skin may serve as an important marker of an emerging hematologic disorder, so close collaboration and multidisciplinary input remain essential to provide optimal and timely care for these patients.

Management of classical Philadelphia chromosome-negative myeloproliferative neoplasms in Asia: consensus of the Asian Myeloid Working Group

Myeloproliferative neoplasms (MPN) are a heterogeneous group of clonal hematopoietic stem cell disorders characterized clinically by the proliferation of one or more hematopoietic lineage(s). The classical Philadelphia-chromosome (Ph)-negative MPNs include polycythemia vera (PV), essential thrombocythemia (ET) and primary myelofibrosis (PMF). The Asian Myeloid Working Group (AMWG) comprises representatives from fifteen Asian centers experienced in the management of MPN. This consensus from the AMWG aims to review the current evidence in the risk stratification and treatment of Ph-negative MPN, to identify management gaps for future improvement, and to offer pragmatic approaches for treatment commensurate with different levels of resources, drug availabilities and reimbursement policies in its constituent regions. The management of MPN should be patient-specific and based on accurate diagnostic and prognostic tools. In patients with PV, ET and early/prefibrotic PMF, symptoms and risk stratification will guide the need for early cytoreduction. In younger patients requiring cytoreduction and in those experiencing resistance or intolerance to hydroxyurea, recombinant interferon-α preparations (pegylated interferon-α 2A or ropeginterferon-α 2b) should be considered. In myelofibrosis, continuous risk assessment and symptom burden assessment are essential in guiding treatment selection. Allogeneic hematopoietic stem cell transplantation (allo-HSCT) in MF should always be based on accurate risk stratification for disease-risk and post-HSCT outcome. Management of classical Ph-negative MPN entails accurate diagnosis, cytogenetic and molecular evaluation, risk stratification, and treatment strategies that are outcome-oriented (curative, disease modification, improvement of quality-of-life).

Contribution of lowered hemoglobin threshold value in the diagnosis of polycythemia vera: Comparison of 2016 and 2008 WHO criteria

Polycythemia vera (PV) diagnosis remains a difficult task despite various updates in the 2016 World Health Organization (WHO) diagnostic criteria compared to 2008 criteria. This study aimed to examine the biochemical and clinical features of patients diagnosed with PV using the WHO 2016 criteria but would have been missed by the WHO 2008 criteria, and to ascertain the impact of the lowered thresholds on PV diagnosis. A total of 229 patients with suspected myeloproliferative neoplasms were included in this cross sectional study. The study group was divided with regard to hemoglobin values. Group A consisted of 126 patients with hemoglobin values of ≤ 18.5 g/dL in males and ≤ 16.5 g/dL in females. Group B comprised 103 patients with hemoglobin values of > 18.5 g/dL in males and > 16.5 g/dL in females. The number of PV diagnoses increased to 145 from 87 (increased by 66.67%) when the 2016 diagnostic criteria were employed rather that the 2008 criteria. Mean age and the frequency of female subjects were lower in Group A compared to Group B. The groups were similar in terms of chronic obstructive pulmonary disease/obstructive sleep apnea syndrome, spleen status, smoking status, and mean corpuscular volume, white blood count, neutrophil, eosinophil and platelet values. red blood cells and lactate dehydrogenase values were significantly higher, while lymphocyte counts were significantly lower in Group B. With the introduction of WHO 2016 criteria, we found a significant increase in the number of patients who were candidates for PV testing and were ultimately diagnosed with PV. These findings support the diagnostic value of the 2016 WHO criteria, and by extension, the lowered thresholds for detection of patients requiring further analysis.

Bomedemstat as an investigative treatment for myeloproliferative neoplasms

INTRODUCTION

Myeloproliferative neoplasm (MPN) is a heterogeneous group of hematopoietic stem cell disorders characterized by clonal proliferation of one of more of the hematopoietic stem cell lineages. Clinical manifestations result from uncontrolled myeloproliferation, extramedullary hematopoiesis with splenomegaly and excessive inflammatory cytokine production. Currently available therapy improves hematologic parameters and symptoms but does not adequately address the underlying neoplastic biology. Bomedemstat has thus far demonstrated clinical efficacy and tolerability in the treatment of MPNs with recent evidence of impacting the malignant stem cell population.

AREAS COVERED

This review summarizes the mechanisms of action, pharmacokinetics and pharmacodynamics, safety and efficacy of bomedemstat in MPN with specific emphasis on essential thrombocythemia (ET) and myelofibrosis (MF).

EXPERT OPINION

In patients with MPNs, bomedemstat appears effective and well tolerated. The signs and symptoms of these diseases are managed as a reduction in the frequency of mutant cells was demonstrated in patients with ET and MF. Ongoing and planned studies of bomedemstat in MPN will establish the position of bomedemstat in MPNs and may help to redefine treatment endpoints of MPNs in the future.

Monitoring longitudinal disease progression in a novel murine Kit tumor model using high-field MRI

Animal models are an indispensable platform used in various research disciplines, enabling, for example, studies of basic biological mechanisms, pathological processes and new therapeutic interventions. In this study, we applied magnetic resonance imaging (MRI) to characterize the clinical picture of a novel N-ethyl-N-nitrosourea-induced Kit-mutant mouse in vivo. Seven C3H Kit^N824K/WT mutant animals each of both sexes and their littermates were monitored every other month for a period of twelve months. MRI relaxometry data of hematopoietic bone marrow and splenic tissue as well as high-resolution images of the gastrointestinal organs were acquired. Compared with controls, the mutants showed a dynamic change in the shape and volume of the cecum and enlarged Peyer´s patches were identified throughout the entire study. Mammary tumors were observed in the majority of mutant females and were first detected at eight months of age. Using relaxation measurements, a substantial decrease in longitudinal relaxation times in hematopoietic tissue was detected in mutants at one year of age. In contrast, transverse relaxation time of splenic tissue showed no differences between genotypes, except in two mutant mice, one of which had leukemia and the other hemangioma. In this study, in vivo MRI was used for the first time to thoroughly characterize the evolution of systemic manifestations of a novel Kit-induced tumor model and to document the observable organ-specific disease cascade.

Thrombosis in myeloproliferative neoplasms during cytoreductive and antithrombotic drug treatment

A state-of-the-art lecture titled "Myeloproliferative Neoplasm-associated Thrombosis" was presented at the ISTH congress in 2021. We summarize here the main points of the lecture with two purposes: to report the incidence rates of major thrombosis in polycythemia vera and essential thrombocythemia and to discuss to what extent cytoreductive therapy and antithrombotic drugs have reduced the incidence of these events. Unfortunately, the incidence rate of thrombosis remains high, ranging between 2 and 5/100 person-years. It is likely that new drugs such as interferon and ruxolitinib can be more efficacious given their cytoreductive and anti-inflammatory activities. Despite prophylaxis with vitamin K antagonists and direct oral anticoagulants after venous thrombosis in either common sites or splanchnic or cerebral sites, the incidence rate is still elevated, as high as 4 to 5/100 person-years. Future studies with new drugs or new strategies should consider thrombosis as the primary endpoint or surrogate biomarkers only if previously validated.

MTAP-related increased erythroblast proliferation as a mechanism of polycythaemia vera

Polycythaemia vera (PV) is a haematological disorder caused by an overproduction of erythroid cells. To date, the molecular mechanisms involved in the disease pathogenesis are still ambiguous. This study aims to identify aberrantly expressed proteins in erythroblasts of PV patients by utilizing mass spectrometry-based proteomic analysis. Haematopoietic stem cells (HSCs) were isolated from newly-diagnosed PV patients, PV patients who have received cytoreductive therapy, and healthy subjects. In vitro erythroblast expansion confirmed that the isolated HSCs recapitulated the disease phenotype as the number of erythroblasts from newly-diagnosed PV patients was significantly higher than those from the other groups. Proteomic comparison revealed 17 proteins that were differentially expressed in the erythroblasts from the newly-diagnosed PV patients compared to those from healthy subjects, but which were restored to normal levels in the patients who had received cytoreductive therapy. One of these proteins was S-methyl-5′-thioadenosine phosphorylase (MTAP), which had reduced expression in PV patients’ erythroblasts. Furthermore, MTAP knockdown in normal erythroblasts was shown to enhance their proliferative capacity. Together, this study identifies differentially expressed proteins in erythroblasts of healthy subjects and those of PV patients, indicating that an alteration of protein expression in erythroblasts may be crucial to the pathology of PV.

Hereditary hemochromatosis and JAK2-positive polycythemia vera

A 59-year-old man was diagnosed with JAK2-positive polycythemia vera. Subsequently, further laboratory testing revealed elevated ferritin and iron saturation. Genetic testing for HFE gene mutation screen revealed that the patient was positive for heterozygous C282Y mutation. The patient was ultimately diagnosed with both polycythemia vera and hereditary hemochromatosis.

Head and Neck Reconstruction in Patients with Polycythemia Vera: Case Series and Literature Review

Background  Polycythemia vera (PV) is a myeloproliferative disease with overproduction of erythrocytes, leukocytes, and platelets causing an increased risk of both thrombosis and hemorrhage. There are limited reports and no established guidelines for managing such patients undergoing reconstructive surgery. Methods  We present four patients with PV and head and neck cancer who required reconstruction after resection and provide a review of the current literature. Results  Preoperatively, patients on cytoreductive therapy continued with their treatment throughout their hospital course and had hematologic parameters normalized with phlebotomy or transfusions if needed. Two patients who underwent free flap surgery (cases 1 and 2) had postoperative courses complicated by hematoma formation and persistent anemia, requiring multiple transfusions. Cases 3 and 4 (JAK2+ PV and JAK2- PV, respectively) underwent locoregional flap without postoperative complications. Conclusion  Concomitant presentation of PV and head and neck cancer is uncommon and presents unique challenges for the reconstructive surgeon. Overall, we recommend that patients should have hematologic parameters optimized prior to surgery, continue ruxolitinib or hydroxyurea, and hold antiplatelet/anticoagulation per established department protocols. It is essential to engage a multidisciplinary team involving hematology, head and neck and reconstructive surgery, anesthesia, and critical care to develop a standardized approach for managing this unique subset of patients.

Subdural Hemorrhage Due to Acquired Von Willebrand Syndrome in a Patient With Polycythemia Vera

Polycythemia vera (PV) is a chronic myeloproliferative neoplasm associated with thrombosis. A 48-year-old female with PV presented with right eye pain following a low-impact head trauma. She consumed aspirin for analgesia and took preparations of Chinese herbs. CT head revealed right-sided subdural hematoma. She had reduced Von Willebrand activity to 26%. Direct angiographic imaging showed an aneurysm arising from a right middle cerebral atery (MCA) branch. The patient was given 1-deamino-8-D-arginine vasopressin (DDAVP) prior to the craniotomy. Intra-operative examination revealed that the aneurysm-like structure was a small grape-like structure of the fibrinous part of the subdural membrane that had formed from the subdural hematoma. Acquired von Willebrand syndrome (AVWS) is an important risk factor for bleeding in PV. DDAVP may be useful to increase levels of Von Willebrand Factor (VWF) and decrease the risk of bleeding perioperatively. Exogenous substances such as ginseng should be investigated as possible contributors to bleeding tendency and discontinued.

Multiple myeloma and primary erythrocytosis in a dog

A 13-year-old spayed female mixed breed dog was referred for impaired ambulation, limb tremors, back pain, hypergammaglobulinemia on cellulose acetate electrophoresis, and mild proteinuria. Conventional radiology and magnetic resonance imaging (MRI) suggested multifocal neoplastic bone lesions. At the referral examination, lameness and bright red mucous membranes were observed. Severe erythrocytosis, a monoclonal peak in the β-2 globulin detected by capillary zone electrophoresis, severe proteinuria, bone marrow infiltration of plasma cells, and low serum erythropoietin concentrations were reported. The final diagnosis was multiple myeloma associated with severe primary erythrocytosis. This presentation in a dog is interesting because the combination of both disorders is rare in humans and has not been reported in dogs. Key clinical message: Although rare, multiple myeloma and primary erythrocytosis can occur together in dogs.

Comparative assessment of outcomes and adverse effects using two different intramuscular testosterone therapy regimens: 100 mg IM weekly or 200 mg IM biweekly

This study aimed to compare the change in levels of several laboratory values and the development of adverse events using two commonly used intramuscular testosterone therapy regimens. Men were included if they were 18 years or older and received one of the following testosterone therapy regimens: 100 mg intramuscular once weekly or 200 mg intramuscular once every other week. Primary outcomes were relative changes in total testosterone, free testosterone, estradiol, prostate-specific antigen, and hematocrit at 6 months after initiation of testosterone therapy. Secondary outcomes were any significant rises in estradiol, hematocrit, prostate-specific antigen, and any other treatment-related adverse events requiring cessation of testosterone therapy. A total of 263 men were enrolled. In a subanalysis of men who had a baseline hematocrit below 54% before intramuscular testosterone therapy initiation, we found the following: men who received 100 mg weekly injections were significantly less likely to have hematocrit levels rising above 54% (1/102 (1%) vs. 4/51 (8%); p = 0.023). No significant differences were recorded in the increase in total testosterone, free testosterone, prostate-specific antigen, and estradiol levels between both groups. A higher average serum testosterone over the dosing interval seen with the 200 mg regimen appears to be associated with a higher risk of erythrocytosis.

Repeat exit site infection in peritoneal dialysis patient with polycythemia vera - a case report

BACKGROUND

Infectious complications of peritoneal dialysis (PD) remain a common cause of catheter loss and discontinuation of PD. Exit site infection (ESI) constitutes a significant risk factor for PD-related peritonitis and determination of predisposing states is relevant. We here present a case of repeat ESI due to Pseudomonas aeruginosa in a PD patient with skin changes in the course of polycythemia vera (PV).

CASE PRESENTATION

A 73-year-old PD patient with chronic kidney disease secondary to renal amyloidosis and ankylosing spondylitis, presented to the nephrology unit with signs of ESI. In 2006 he was diagnosed with PV and since then has was successfully treated with hydroxyurea; however, he reported recurrent episodes of developing skin nodules in the course of the disease. Exit site swab yielded Pseudomonas aeruginosa and the infection developed in the ulcerated PV nodule that appeared in exit site 2 weeks earlier. Patient was treated with intraperitoneal amikacin and oral ciprofloxacin, however, due to neurological complications, the treatment had to be interrupted and finally catheter was removed. Similar episode of ESI with Pseudomonas aeruginosa developed in the patient two years earlier and also required catheter removal.

CONCLUSION

This is the first case report demonstrating the development of ESI on the polycythemia vera skin lesion in this area. Skin manifestations of PV might be a predisposing factor to ESI in PD patients.

Macroscopic Hematuria as the Initial Presentation of Polycythemia Vera

Polycythemia vera (PV) is a chronic myeloproliferative neoplasm (CMN) characterized by the accumulation of red blood cells, granulocytes and platelets in the peripheral blood. The main complications of PV are an increased risk of thrombosis, bleeding and transformation to myelodysplasia or acute leukemia. The authors report the case of a 28-year-old man with a complaint of macroscopic hematuria, low back pain and edema of the left arm associated with elevated hemoglobin, hematocrit and lactic dehydrogenase, leukocytosis and increased renal volume. Computed tomography of the chest and abdomen with contrast showed venous ectasia in the left upper limb and thrombosis of the right renal vein with extension to the inferior vena cava. A diagnosis of PV was confirmed by the presence of the JAK2 mutation and a bone marrow biopsy that showed panmyelosis. The patient was anticoagulated and treatment for PV was started with aspirin, phlebotomy and hydroxyurea. Then, the patient was discharged for outpatient follow-up with a hematologist. The case emphasizes the importance of clinical suspicion for atypical presentation of the disease in an unusual age range and of adequate etiological investigation of thrombosis in unusual sites.