Myeloproliferative Neoplasms, Version 3.2022, NCCN Clinical Practice Guidelines in Oncology

SOHO State of the Art Updates and Next Questions | Diagnosis, Outcomes, and Management of Prefibrotic Myelofibrosis

Prefibrotic primary myelofibrosis (prefibrotic PMF) is a myeloproliferative neoplasm with distinct characteristics comprising histopathological and clinico-biological parameters. It is classified as a subtype of primary myelofibrosis. In clinical practice, it is essential to correctly distinguish prefibrotic PMF from essential thrombocythemia especially but also overt PMF besides other myeloid neoplasms. Risk stratification and survival outcomes for prefibrotic PMF are worse than that of ET but better than that of overt PMF. Rates of progression to overt PMF and blast phase disease are also higher for prefibrotic PMF than ET. In this review we first discuss the historical context to the evolution of prefibrotic PMF as an entity, its presenting features and diagnostic criteria. We emphasize the differences between prefibrotic PMF, ET, and overt PMF with regards to presenting features and disease outcomes including thrombohemorrhagic events and progression to fibrotic and blast phase disease. Next, we discuss the risk stratification models and contextualize these in the setting of clinical management. We share our view of personalizing treatment to address unique patient needs in the context of currently available management options. Lastly, we discuss areas of critical need in clinical research and speculate on the possibility of future disease course modifying therapies in prefibrotic PMF.

Myelofibrosis and allogeneic transplantation: critical points and challenges

New available drugs allow better control of systemic symptoms associated with myelofibrosis (MF) and splenomegaly but they do not modify the natural history of progressive and poor prognosis disease. Thus, hematopoietic stem cell transplantation (HSCT) is still considered the only available curative treatment for patients with MF. Despite the increasing number of procedures worldwide in recent years, HSCT for MF patients remains challenging. An increasingly complex network of the patient, disease, and transplant-related factors should be considered to understand the need for and the benefits of the procedure. Unfortunately, prospective trials are often lacking in this setting, making an evidence-based decision process particularly arduous. In the present review, we will analyze the main controversial points of allogeneic transplantation in MF, that is, the development of more sophisticated models for the identification of eligible patients; the need for tools offering a more precise definition of expected outcomes combining comorbidity assessment and factors related to the procedure; the decision-making process about the best transplantation time; the evaluation of the most appropriate platform for curative treatment; the impact of splenomegaly; and splenectomy on outcomes.

Translation, Cultural Adaptation, and Validation into Romanian of the Myeloproliferative Neoplasm Symptom Assessment Form-Total Symptom Score (MPN-SAF TSS or MPN-10) Questionnaire

Background: Patients with myeloproliferative neoplasms (MPNs) experience a high disease-related symptom burden. A specific instrument to evaluate quality of life (QoL), i.e., the MPN Symptom Assessment Form Total Symptom Score (MPN-SAF TSS; MPN-10), was developed. We conducted the translation, cultural adaptation, and validation into Romanian of the MPN-10. Methods: We translated the MPN-10 and tested its psychometric properties. Results: We recruited 180 MPN patients: 66 polycythemia vera (36.67%), 61 essential thrombocythemia (33.89%), 51 primary and secondary myelofibrosis (SMF) (28.33%), and 2 MPN-unclassifiable (1.11%). The mean TSS was 19.51 ± 16.51 points. Fatigue, inactivity, and concentration problems were the most cumbersome symptoms. We detected scoring differences between MPN subtypes regarding weight loss (p < 0.001), fatigue (p = 0.006), early satiety (p = 0.007), night sweats (p = 0.047), pruritus (p = 0.05), and TSS (p = 0.021). There were strong positive associations between TSS and inactivity, fatigue, and concentration problems, and moderate negative correlations between QoL scores and all MPN-10 items. Cronbach's α internal consistency coefficient was 0.855. The Kaiser-Meyer-Olkin construct validity test result was 0.870 and the Bartlett Sphericity Test was significant (p < 0.001). Symptom scores were loaded into one single factor according to the exploratory factor analysis. Conclusions: The Romanian MPN-10 version displayed excellent psychometric properties and is a reliable instrument for assessing symptom burden and QoL in Romanian MPN patients.

Methodological challenges in the development of endpoints for myelofibrosis clinical trials

Myelofibrosis is a myeloid neoplasm characterised by the presence of JAK2, CALR, or MPL mutations (with a 90% mutation frequency) and trilineage myeloid proliferation with prominent megakaryocyte atypia. People with myelofibrosis have a lower survival rate and poorer quality of life than healthy individuals. Therapy for myelofibrosis uses Janus kinase inhibitors, which reduce splenomegaly and alleviate symptoms. Regulatory approvals for Janus kinase inhibitors have focused on this dual endpoint. In this Viewpoint, we discuss the validity of using spleen reduction as a surrogate endpoint for the disease-modifying activity of candidate drugs for myelofibrosis. We suggest alternative endpoints addressing unmet patient needs, including progression-free survival and overall survival. Moreover, we highlight the importance of selecting a core set of crucial outcomes with which we can individualise clinical decision making and standardise reporting of clinical trials results. We propose selecting patient-reported outcomes and anaemia response. We also suggest integrating economic considerations in the process of evaluating new drugs for myelofibrosis.

ADAMTS13, von Willebrand Factor, Platelet Microparticles, Factor VIII, and Impact of Somatic Mutations in the Pathogenesis of Splanchnic Vein Thrombosis Associated with BCR-ABL-Negative Myeloproliferative Neoplasms

BACKGROUND

Myeloproliferative neoplasms (MPNs) are often associated with splanchnic vein thrombosis (SVT). Not all the factors involved in the thrombotic tendency are currently known.

OBJECTIVES

This study aims to evaluate a possible association between ADAMTS13, von Willebrand factor (VWF), platelet microvesicles (MV), and factor VIII activity (FVIII:C) with thrombotic events in MPN patients.

MATERIALS AND METHODS

In total, 36 consecutive MPN patients with SVT were enrolled. The MPNs were diagnosed based on clinical characteristics and one or more gene mutations among JAK-2, CALR, and MPL. As controls, 50 randomly selected patients with MPN without thrombosis, 50 patients with deep vein thrombosis without MPNs, and 50 healthy blood donors were evaluated. Complete blood count, ADAMTS13, VWF, MV, and FVIII:C in plasma were measured in all the subjects.

RESULTS

The JAK-2 mutation was found in 94% of the patients with SVT, but none were triple-negative for genetic mutations (JAK2 V617F, CALR, MPL, and exon 12). Compared to the normal subjects, in all the MPN patients (with or without SVT), the levels of ADAMTS13 were found to be significantly lower (p < 0.001) and the MV concentrations were significantly higher (p < 0.001). Among the MPN patients, the VWF and FVIII:C levels were significantly higher in the patients with SVT than those without thrombosis (p = 0.007 and p = 0.04, respectively). Splenomegaly was present in 78% of MPN patients with SVT and in 30% of those without SVT (p < 0.001). The ADAMTS13/VWF ratio was reduced in all the patients, but not in the healthy blood donors (p < 0.001).

CONCLUSIONS

The significant increase in circulating MV, VWF, and FVIII:C in the MPN patients and in the patients with thrombosis supports the role of endothelium damage in promoting thrombotic events. In particular, a significant increase in VWF and FVIII:C levels was found in the MPN patients with SVT.

Analytical Performance Evaluation of a Digital Real-Time PCR for Quantifying Major BCR::ABL1 Transcripts

BACKGROUND

Accurate quantification of the BCR::ABL1 transcripts is essential for measurable residual disease (MRD) monitoring in chronic myeloid leukemia (CML) after tyrosine kinase inhibitor (TKI) treatment. This study evaluated the newly developed digital real-time PCR method, Dr. PCR, as an alternative reverse transcription-PCR (qRT-PCR) for MRD detection.

METHODS

The performance of Dr. PCR was assessed using reference and clinical materials. Precision, linearity, and correlation with qRT-PCR were evaluated. MRD levels detected by Dr. PCR were compared with qRT-PCR, and practical advantages were investigated.

RESULTS

Dr. PCR detected MRD up to 0.0032%IS (MR4.5) with excellent precision and linearity and showed a strong correlation with qRT-PCR results. Notably, Dr. PCR identified higher levels of MRD in 12.7% (29/229) of patients than qRT-PCR, including six cases of MR4, which is a critical level for TKI discontinuation. Dr. PCR also allowed for sufficient ABL1 copies in all cases, while qRT-PCR necessitated multiple repeat tests in 3.5% (8/229) of cases.

CONCLUSION

Our study provides a body of evidence supporting the clinical application of Dr. PCR as a rapid and efficient method for assessing MRD in patients with CML under the current treatment regimen.

Ropeginterferon phase 2 randomized study in low-risk polycythemia vera: 5-year drug survival and efficacy outcomes

In patients with low-risk polycythemia vera, exposure to low-dose Ropeginterferon alfa-2b (Ropeg) 100 µg every 2 weeks for 2 years was more effective than the standard treatment of therapeutic phlebotomy in maintaining target hematocrit (HCT) (< 45%) with a reduction in the need for phlebotomy without disease progression. In the present paper, we analyzed drug survival, defined as a surrogate measure of the efficacy, safety, adherence, and tolerability of Ropeg in patients followed up to 5 years. During the first 2 years, Ropeg and phlebotomy-only (Phl-O) were discontinued in 33% and 70% of patients, respectively, for lack of response (12 in the Ropeg arm vs. 34 in the Phl-O arm) or adverse events (6 vs. 0) and withdrawal of consent in (3 vs. 10). Thirty-six Ropeg responders continued the drug for up to 3 years, and the probability of drug survival after a median of 3.15 years was 59%. Notably, the primary composite endpoint was maintained in 97%, 94%, and 94% of patients still on drug at 3, 4, and 5 years, respectively, and 60% of cases were phlebotomy-free. Twenty-three of 63 Phl-O patients (37%) failed the primary endpoint and were crossed over to Ropeg; among the risk factors for this failure, the need for more than three bloodletting procedures in the first 6 months emerged as the most important determinant. In conclusion, to improve the effectiveness of Ropeg, we suggest increasing the dose and using it earlier driven by high phlebotomy need in the first 6 months post-diagnosis.

A germline JAK2 exon12 mutation and a late somatic CALR mutation in a patient with essential thrombocythemia

Background

It has been discovered that Janus kinase 2 (JAK2) exon12 mutations lead to the polycythemia vera (PV) phenotype, while somatic mutations of calreticulin (CALR) are associated with essential thrombocythemia (ET) or primary myelofibrosis. In this article, we report a case of ET with coexistence of JAK2 exon12 and CALR mutations. The objective of this study was to elucidate the pathogenicity mechanism of a JAK2 exon12 mutation (JAK2N533S) and the role of the coexistence of mutations on the hematological phenotype.

Methods

We designed a colony analysis of tumor cells obtained from this patient, and attempted to identify mutant genes using DNA from hair follicles. Mutation impairment prediction and conservative analysis were conducted to predict the mutation impairment and structure of JAK2N533S. In addition, we conducted a functional analysis of JAK2N533S by constructing Ba/F3 cell models.

Results

Three distinct tumor subclones, namely JAK2N533Shet+/CALRtype1het +, JAK2N533Shet+/CALR wt, and JAK2N533Shet+/CALRtype1hom +, were identified from the 17 selected erythroid and 21 selected granulocyte colonies. The analysis of hair follicles yielded positive results for JAK2N533S. According to the bioinformatics analysis, JAK2N533S may exert only a minor effect on protein function. Functional studies showed that JAK2N533S did not have a significant effect on the proliferation of Ba/F3 cells in the absence of interleukin-3 (IL-3), similar to wild-type JAK2. Notably, there were no increased phosphorylation levels of JAK2-downstream signaling proteins, including signal transducer and activator of transcription 3 (STAT3) and STAT5, in Ba/F3 cells harboring the JAK2N533S.

Conclusion

Our study revealed that the JAK2N533Shet+/CALRtype1het+ subclone was linked to a significant expansion advantage in this patient, indicating that it may contribute to the development of the ET phenotype. We further demonstrated that JAK2N533S, as a noncanonical JAK2 exon12 mutation, is a germline mutation that may not exert an effect on cell proliferation and protein function. These results and the present body of available data imply that certain noncanonical JAK2 mutations are not gain-of-function mutations leading to the development of myeloproliferative neoplasms.

A safety evaluation of ruxolitinib for the treatment of polycythemia vera

INTRODUCTION

Polycythemia Vera (PV) is a chronic myeloproliferative neoplasm hallmarked by deregulated proliferation of hematopoietic stem cells leading to prevalent expansion of red cell mass, increased rate of vascular events, splenomegaly, disease-associated symptoms, and risk of evolution to secondary myelofibrosis and blast phase. PV is pathogenetically associated with autonomously persistent activation of JAK2, which causes overproduction of blood cells and an inflammatory condition responsible for the clinical manifestations of the disease. Extensively supported by preclinical studies, targeting JAK2-dependent signaling represents a rational therapeutic approach to PV, finally leading to the approval of ruxolitinib, a JAK1/2 inhibitor.

AREAS COVERED (LITERATURE RESEARCH)

We analyzed reports of phase 2 and phase 3 trials with ruxolitinib in PV and relevant literature dealing with efficacy and safety aspects, including most recent real-world reports.

EXPERT OPINION

Ruxolitinib is the only JAK2 inhibitor approved for the treatment of PV with well-known efficacy for splenomegaly, symptoms, and potentially reduction of vascular events. The treatment regimen is notably manageable and safe, with the most prevalent side effects primarily encompassing myelosuppression, hyperlipidemia, non-melanoma skin cancer and infections, mainly reactivation of Herpes Zoster. These effects necessitate ongoing surveillance and proactive preventive measures.

Discontinuation Syndrome With JAK2 Selective Agents: Case Presentation and Mechanistic Insights

We report the first case of pacritinib-withdrawal syndrome with in vitro elucidation of underlying mechanisms.

Cost in the United States of FDA-approved small molecule protein kinase inhibitors used in the treatment of neoplastic and non-neoplastic diseases

Because genetic alterations including mutations, overexpression, translocations, and dysregulation of protein kinases are involved in the pathogenesis of many illnesses, this enzyme family is the target of many drug discovery programs worldwide. The FDA has approved 80 small molecule protein kinase inhibitors with 77 drugs orally bioavailable. The data indicate that 69 of these medicinals are approved for the management of neoplasms including solid tumors such as breast and lung cancer as well as non-solid tumors such as leukemia. Moreover, the remaining 11 drugs target non-neoplastic diseases including psoriasis, rheumatoid arthritis, and ulcerative colitis. The cost of drugs was obtained from www.pharmacychecker.com using the FDA label to determine the dosage and number of tablets required per day. This methodology excludes any private or governmental insurance coverage, which would cover the entire cost or more likely a fraction of the stated price. The average monthly cost for the treatment of neoplastic diseases was $17,900 with a price of $44,000 for futibatinib (used to treat cholangiocarcinomas with FGFR2 fusions) and minimum of $5100 for binimetinib (melanoma). The average monthly cost for the treatment of non-neoplastic diseases was $6800 with a maximum of $17,000 for belumosudil (graft vs. host disease) and a minimum of $200 for netarsudil eye drops (glaucoma). There is a negative correlation of the cost of the drugs and the incidence of the targeted disease. Many of these agents are or were designated as orphan drugs meaning that there are fewer than 200,000 potential patients in the United States.

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).

Moving toward disease modification in polycythemia vera

Polycythemia vera (PV) belongs to the BCR-ABL1-negative myeloproliferative neoplasms and is characterized by activating mutations in JAK2 and clinically presents with erythrocytosis, variable degrees of systemic and vasomotor symptoms, and an increased risk of both thromboembolic events and progression to myelofibrosis and acute myeloid leukemia (AML). Treatment selection is based on a patient's age and a history of thrombosis in patients with low-risk PV treated with therapeutic phlebotomy and aspirin alone, whereas cytoreductive therapy with either hydroxyurea or interferon alfa (IFN-α) is added for high-risk disease. However, other disease features such as significant disease-related symptoms and splenomegaly, concurrent thrombocytosis and leukocytosis, or intolerance of phlebotomy can constitute an indication for cytoreductive therapy in patients with otherwise low-risk disease. Additionally, recent studies demonstrating the safety and efficacy (ie, reduction in phlebotomy requirements and molecular responses) of ropegylated IFN-α2b support its use for patients with low-risk PV. Additionally, emerging data suggest that early treatment is associated with higher rates of molecular responses, which might eventually enable time-limited therapy. Nonetheless, longer follow-up is needed to assess whether molecular responses associate with clinically meaningful outcome measures such as thrombosis and progression to myelofibrosis or AML. In this article, we provide an overview of the current and evolving treatment landscape of PV and outline our vision for a patient-centered, phlebotomy-free, treatment approach using time-limited, disease-modifying treatment modalities early in the disease course, which could ultimately affect the natural history of the disease.

Safety and efficacy of jaktinib (a novel JAK inhibitor) in patients with myelofibrosis who are relapsed or refractory to ruxolitinib: A single-arm, open-label, phase 2, multicenter study

Ruxolitinib has demonstrated efficacy in patients with myelofibrosis (MF). However, substantial number of patients may not respond after 3-6 months of treatment or develop resistance over time. In this phase 2 trial, patients with a current diagnosis of intermediate or high-risk MF who either had an inadequate splenic response or spleen regrowth after ruxolitinib treatment were enrolled. All patients received jaktinib 100 mg Bid. The primary endpoint was the proportion of patients with ≥35% reduction in spleen volume (SVR 35) at week 24. The secondary endpoints included change of MF-related symptoms, anemic response, and safety profile. From July 6, 2021, to January 24, 2022, 34 ruxolitinib-refractory or relapsed patients were enrolled, 52.9% (18 of 34) were DIPSS intermediate 2 or high risk. SVR 35 at week 24 was 32.4% (11 of 34, 95% CI 19.1%-49.2%) in all patients and 33.3% (6 of 18, 95% CI 16.3%-56.3%) in the intermediate 2 or high-risk group. A total of 50% (8 of 16) transfusion-independent patients with hemoglobin (HGB) <100 g/L at baseline had HGB elevation ≥20 g/L within 24 weeks. Furthermore, 46.4% (13 of 28) of patients had a ≥ 50% decrease in the total symptom score (TSS 50) at week 24. The most common grade ≥3 treatment-emergent adverse events (TEAEs) were thrombocytopenia (32.4%), anemia (32.4%), and leukocytosis (20.6%). In total, 13 (38.2%) of 34 patients had serious adverse events (SAE), of which drug-related SAEs were found in 5 patients (14.7%). These results indicate that jaktinib can be a promising treatment option for patients with MF who have either become refractory to or relapsed after ruxolitinib treatment.

Statin use, survival and incidence of thrombosis among older patients with polycythemia vera and essential thrombocythemia

BACKGROUND

Polycythemia vera (PV) and essential thrombocythemia (ET) are linked to increased risk of cardiovascular morbidity and mortality. In addition to the reduction in of arterial thrombotic events, statins may prevent venous thrombosis including among patients with cancer. As previous registry- and claims-based studies revealed that the use of statins may improve the survival of patients with various malignancies we evaluated their impact on outcomes of older adults with PV and ET.

METHODS

We identified 4010 older adults (aged 66-99 years at diagnosis) with PV (n = 1809) and ET (n = 2201) in a population-based cohort study using the Surveillance, Epidemiology, and End Results-Medicare database with median follow-up of 3.92 (interquartile range: 2.58-5.75) years. Propensity score matching (PSM) and inverse probability of treatment weighting (IPTW) approaches were utilized to assess potential association between statins and overall survival. Multivariable competing risk models with death as a competing risk were used to evaluate possible relationship between statins and the incidence of thrombosis.

RESULTS

55.8% of the patients used statins within the first year after PV/ET diagnosis, and statin use was associated with a 22% reduction in all-cause mortality (PSM: hazard ratio [HR] = 0.78, 95% confidence interval [CI]: 0.63-0.98, p = 0.03; IPTW: HR = 0.79, 95% CI: 0.64-0.97, p = 0.03). Statins also reduced the risk of thrombosis in this patient population (PSM: HR = 0.63, 95% CI: 0.51-0.78, p < 0.01; IPTW: HR = 0.57, 95% CI: 0.49-0.66, p < 0.01) as well as in PV and ET subgroups.

CONCLUSIONS

These findings suggest that it may be important to incorporate statins into the therapeutic strategy for older adults with PV and ET.

Cost-effectiveness of ropeginterferon alfa-2b-njft for the treatment of polycythemia vera

Aim: Patients with polycythemia vera (PV), a rare and chronic blood cancer, are at a higher risk for thromboembolic events, progression to myelofibrosis, and leukemic transformation. In 2021, ropeginterferon alfa-2b-njft (BESREMi®) was approved in the US to treat adults with PV. The purpose of this study is to estimate the cost-effectiveness of ropeginterferon alfa-2b-njft, used as a first- or second-line treatment, for the treatment of patients with PV in the US. Materials & methods: A Markov cohort model was developed from the healthcare system perspective in the United States. Model inputs were informed by the PROUD-PV and CONTINUATION-PV studies and published literature. The model population included both low-risk and high-risk patients with PV. The model compared ropeginterferon alfa-2b-njft used either as first- or second-line versus an alternative treatment pathway of first-line hydroxyurea followed by ruxolitinib. Results: Over the modeled lifetime, ropeginterferon alfa-2b-njft provided an additional 0.4 higher quality-adjusted life years (QALYs) and 0.4 life-years with an added cost of USD60,175, resulting in a cost per QALY of USD141,783. The model was sensitive to treatment costs, the percentage of patients who discontinue hydroxyurea, the percentage of ropeginterferon alfa-2b-njft users who switch to monthly dosing, the percentage of ropeginterferon alfa-2b-njft users as 2nd line treatment, and the treatment response rates. A younger patient age at baseline and a higher percentage of patients with low-risk disease improved the cost-effectiveness of ropeginterferon alfa-2b-njft. Conclusion: Ropeginterferon alfa-2b-njft is a cost-effective treatment option for a broad range of patients with PV, including both low- and high-risk patients and patients with and without prior cytoreductive treatment with hydroxyurea.

The pharmacotherapeutic management of patients with myelofibrosis: looking beyond JAK inhibitors

INTRODUCTION

The approach to myelofibrosis (MF) has been revolutionized in recent years, overcoming the traditional therapies, often not very effective. Janus kinase inhibitors (JAKi - from ruxolitinib up to momelotinib) were the first class of drugs with considerable results.

AREAS COVERED

Ongoing, new molecules are being tested that promise to give hope even to those patients not eligible for bone marrow transplants who become intolerant or are refractory to JAKi, for which therapeutic hopes are currently limited. Telomerase, murine double minute 2 (MDM2), phosphatidylinositol 3-kinase δ (PI3Kδ), BCL-2/xL, and bromodomain and extra-terminal motif (BET) inhibitors are the drugs with promising results in clinical trials and close to closure with consequent placing on the market, finally allowing JAK to look beyond. The novelty of the MF field was searched in the PubMed database, and the recently completed/ongoing trials are extrapolated from the ClinicalTrial website.

EXPERT OPINION

From this point of view, the use of new molecules widely described in this review, probably in association with JAKi, will represent the future treatment of choice in MF, leaving, in any case, the potential new approaches actually in an early stage of development, such as the use of immunotherapy in targeting CALR, which is coming soon.

Incidence of blast phase in myelofibrosis according to anemia severity

Myelofibrosis (MF) is a clonal malignancy frequently characterized by anemia and in 10%-20% of cases it can evolve into blast phase (BP). Anemia in MF is associated with reduced survival and -in primary MF- also with an increased probability of BP. Conventional treatments for anemia have limited effectiveness in MF. Within a dataset of 1752 MF subjects largely unexposed to ruxolitinib (RUX), BP incidence was 2.5% patients per year (p-y). This rate reached respectively 4.3% and 4.5% p-y in case of patients with common terminology criteria for adverse events (CTCAE) grade 3/4 and grade 2 anemia, respectively, that represented together 32% of the cohort. Among 273 MF cases treated with RUX, BP incidence was 2.89% p-y and it reached 4.86% p-y in subjects who started RUX with CTCAE grade 2 anemia (one third of total). Within patients with red blood cell transfusion-dependency at 6 months of RUX (21% of the exposed), BP rate was 4.2% p-y. Our study highlights a relevant incidence of BP in anemic MF patients, with a similar rate whether treated with or without RUX. These findings will help treating physicians to make decisions on the safety profile of innovative anemia treatments.

Essential Thrombocythemia in Adolescents and Young Adults: Clinical Aspects, Treatment Options and Unmet Medical Needs

OPINION STATEMENT

Current treatment of essential thrombocythemia (ET) should primarily prevent thrombo-hemorrhagic events, without increasing the rate of fibrotic progression or leukemic evolution, and secondarily control microvascular symptoms. Unlike other classic BCR::ABL1-negative myeloproliferative neoplasms, ET is frequently diagnosed in adolescents and young adults (AYA), defined as individuals aged 15 to 39 years, in up to 20% of patients. However, since the current risk stratification of this disease is based on models, including that of ELN, IPSET-Thrombosis and its revised version, mainly applied to an older patients' population, international guidelines are needed that specifically consider how to evaluate the prognosis of AYAs with ET. Furthermore, although ET is the most frequent MPN among AYA subjects, there is a lack of specific recommendations on how to treat it in this subgroup of patients, as management decisions are typically extrapolated from those for the elderly. Accordingly, since AYAs with ET represent a unique disease subset defined by attenuated genetic risk, more indolent phenotype, and longer survival than their older counterparts, treatment selection requires special attention to specific issues such as the risk of fibrotic/leukemic transformation, carcinogenicity, and fertility. This review article will provide a comprehensive overview of the diagnosis, prognostic stratification, and possible therapeutic approaches for AYA patients with ET, including antiplatelets/anticoagulants and cytoreductive agents, with a focus on pregnancy management in real-life clinical practice.

Comprehensive profiling of clinical JAK inhibitors in myeloproliferative neoplasms

Small molecule inhibitors targeting JAK2 provide symptomatic benefits for myeloproliferative neoplasm (MPN) patients and are among first-line therapeutic agents. However, despite all having potent capacity to suppress JAK-STAT signaling, they demonstrate distinct clinical profiles suggesting contributory effects in targeting other ancillary pathways. Here, we performed comprehensive profiling on four JAK2 inhibitors either FDA-approved (ruxolitinib, fedratinib, and pacritinib) or undergoing phase 3 studies (momelotinib) to better outline mechanistic and therapeutic efficacy. Across JAK2-mutant in vitro models, all four inhibitors demonstrated similar anti-proliferative phenotypes, whereas pacritinib yielded greatest potency on suppressing colony formation in primary samples, while momelotinib exhibited unique erythroid colony formation sparing. All inhibitors reduced leukemic engraftment, disease burden, and extended survival across patient-derived xenograft (PDX) models, with strongest effects elicited by pacritinib. Through RNA-sequencing and gene set enrichment analyses, differential suppressive degrees of JAK-STAT and inflammatory response signatures were revealed, which we validated with signaling and cytokine suspension mass cytometry across primary samples. Lastly, we assessed the capacity of JAK2 inhibitors to modulate iron regulation, uncovering potent suppression of hepcidin and SMAD signaling by pacritinib. These comparative findings provide insight into the differential and beneficial effects of ancillary targeting beyond JAK2 and may help guide the use of specific inhibitors in personalized therapy.

Evolving cognition of the JAK-STAT signaling pathway: autoimmune disorders and cancer

The Janus kinase (JAK) signal transducer and activator of transcription (JAK-STAT) pathway is an evolutionarily conserved mechanism of transmembrane signal transduction that enables cells to communicate with the exterior environment. Various cytokines, interferons, growth factors, and other specific molecules activate JAK-STAT signaling to drive a series of physiological and pathological processes, including proliferation, metabolism, immune response, inflammation, and malignancy. Dysregulated JAK-STAT signaling and related genetic mutations are strongly associated with immune activation and cancer progression. Insights into the structures and functions of the JAK-STAT pathway have led to the development and approval of diverse drugs for the clinical treatment of diseases. Currently, drugs have been developed to mainly target the JAK-STAT pathway and are commonly divided into three subtypes: cytokine or receptor antibodies, JAK inhibitors, and STAT inhibitors. And novel agents also continue to be developed and tested in preclinical and clinical studies. The effectiveness and safety of each kind of drug also warrant further scientific trials before put into being clinical applications. Here, we review the current understanding of the fundamental composition and function of the JAK-STAT signaling pathway. We also discuss advancements in the understanding of JAK-STAT-related pathogenic mechanisms; targeted JAK-STAT therapies for various diseases, especially immune disorders, and cancers; newly developed JAK inhibitors; and current challenges and directions in the field.

Combination of azacitidine, venetoclax and ruxolitinib in blast phase myeloproliferative neoplasms

Myeloproliferative neoplasms in blastic phase (MPN-BP) have a dreadful prognosis. We report the characteristics and outcomes of five MPN-BP patients treated with a never-before-described combination of azacytidine and venetoclax (to control BP transformation), added to ruxolitinib (needed to control constitutional symptoms). Median age was 76 years (range 72-84), and worst performance status was 2. The overall response rate was 80%, and the complete remission rate was 40%. With median follow-up of 10.0 months (range 4.2-13.4), median overall survival was 13.4 months (95% CI 4.2-13.4). We did not detect any unexpected treatment-related toxicity, and quality of life was improved.

High-resolution melting assay for rapid, simultaneous detection of JAK2, MPL and CALR variants

AIMS

Identification of recurrent genetic alterations in JAK2, MPL and CALR remains crucial in the diagnosis of Philadelphia-negative myeloproliferative neoplasms (MPNs). Current laboratory testing algorithms may entail batching and/or sequential testing, involving multiple testing modalities and sometimes send-out testing that increase the technical and economic demands on laboratories while delaying patient diagnoses. To address this gap, an assay based on PCR and high-resolution melting (HRM) analysis was developed for simultaneous evaluation of JAK2 exons 12-14, MPL exon 10 and CALR exon 9, embodied in the HemeScreen® (hereafter 'HemeScreen') MPN assay.

METHODS

The HemeScreen MPN assay was validated with blood and bone marrow samples from 982 patients with clinical suspicion for MPN. The HRM assay and Sanger sequencing were performed in independent Clinical Laboratory Improvement Amendments (CLIA)-certified laboratories with Sanger sequencing (supported by droplet digital PCR) serving as the gold standard.

RESULTS

HRM and Sanger sequencing had an overall concordance of 99.4% with HRM detecting 133/139 (96%) variants confirmed by sequencing (9/10 MPL, 25/25 CALR, 99/104 JAK2), including 114 single nucleotide variants and 25 indels (3-52 bp). Variants consisted of disease-associated (DA) variants (89%), variants of unclear significance (2%) and non-DA variants (9%) with a positive predictive value of 92.3% and negative predictive value of 99.5%.

CONCLUSIONS

These studies demonstrate the exquisite accuracy, sensitivity and specificity of the HRM-based HemeScreen MPN assay, which serves as a powerful, clinically applicable platform for rapid, simultaneous detection of clinically relevant, somatic disease variants.

Novel therapeutic strategies for essential thrombocythemia/polycythemia vera

Myeloproliferative neoplasms (MPNs) are clonal disorders of hematopoietic stem cells; these include polycythemia vera (PV), essential thrombocythemia (ET), and primary myelofibrosis (PMF). MPNs are inflammatory cancers, wherein the malignant clone generates cytokines that sustain the inflammatory drive in a self-perpetuating vicious cycle. The course of MPNs follows a biological continuum, that is, from early cancer stages (ET/PV) to advanced myelofibrosis as well as impending leukemic transformation. MPN-related symptoms, e.g., fatigue, general weakness, and itching, are caused by inflammatory cytokines. Thrombosis and bleeding are also exacerbated by inflammatory cytokines in patients with MPN. Until recently, the primary objective of ET and PV therapy was to increase survival rates by preventing thrombosis. However, several medications have recently demonstrated the ability to modify the course of the disease; symptom relief is expected for most patients. In addition, there is increasing interest in the active treatment of patients at low risk with PV and ET. This review focuses on the ET/PV treatment strategies as well as novel treatment options for clinical development.

Myelofibrosis

The clinical phenotype of primary and post-polycythemia vera and postessential thrombocythemia myelofibrosis (MF) is dominated by splenomegaly, symptomatology, a variety of blood cell alterations, and a tendency to develop vascular complications and blast phase. Diagnosis requires assessing complete cell blood counts, bone marrow morphology, deep genetic evaluations, and disease history. Driver molecular events consist of JAK2V617F, CALR, and MPL mutations, whereas about 8% to 10% of MF are "triple-negative." Additional myeloid-gene variants are described in roughly 80% of patients. Currently available clinical-based and integrated clinical/molecular-based scoring systems predict the survival of patients with MF and are applied for conventional treatment decision-making, indication to stem cell transplant (SCT) and allocation in clinical trials. Standard treatment consists of anemia-oriented therapies, hydroxyurea, and JAK inhibitors such as ruxolitinib, fedratinib, and pacritinib. Overall, spleen volume reduction of 35% or greater at week 24 can be achieved by 42% of ruxolitinib-, 47% of fedratinib-, 19% of pacritinib-, and 27% of momelotinib-treated patients. Now, it is time to move towards new paradigms for evaluating efficacy like disease modification, that we intend as a robust and unequivocal effect on disease biology and/or on patient survival. The growing number of clinical trials potentially pave the way for new strategies in patients with MF. Translational studies of some molecules showed an early effect on bone marrow fibrosis and on variant allele frequencies of myeloid genes. SCT is still the only curative option, however, it is associated with relevant challenges. This review focuses on the diagnosis, prognostication, and treatment of MF.

JAK2 V617F allele burden in polycythemia vera: burden of proof

Polycythemia vera (PV) is a hematopoietic stem cell neoplasm defined by activating somatic mutations in the JAK2 gene and characterized clinically by overproduction of red blood cells, platelets, and neutrophils; a significant burden of disease-specific symptoms; high rates of vascular events; and evolution to a myelofibrosis phase or acute leukemia. The JAK2V617F variant allele frequency (VAF) is a key determinant of outcomes in PV, including thrombosis and myelofibrotic progression. Here, we critically review the dynamic role of JAK2V617F mutation burden in the pathogenesis and natural history of PV, the suitability of JAK2V617F VAF as a diagnostic and prognostic biomarker, and the utility of JAK2V617F VAF reduction in PV treatment.

Evaluating ropeginterferon alfa-2b for the treatment of adults with polycythemia vera

INTRODUCTION

Interferons (IFNs) have been used for decades to treat polycythemia vera (PV). Single-arm clinical trials assessing IFN in PV patients demonstrated high hematological and molecular response rates, indicating potential disease-modifying activity of IFN. However, discontinuation rates of IFNs have been rather high due to frequent treatment-related side-effects.

AREAS COVERED

Ropeginterferon alfa-2b (ROPEG) is a monopegylated IFN consisting of a single isoform, which differentiates it from previous IFNs with respect to tolerability and dosing frequency. ROPEG has improved pharmacokinetic and pharmacodynamic properties, which allow extended dosing every 2 weeks and monthly administration during maintenance phase. This review covers ROPEG's pharmacokinetic and pharmacodynamic properties, presents results of randomized clinical trials (RCT) that evaluated ROPEG in the treatment of PV patients, and discusses contemporary findings regarding the potential disease-modifying activity of ROPEG.

EXPERT OPINION

RCT have demonstrated high rates of hematological and molecular responses in PV patients treated with ROPEG, irrespective of thrombotic risk. Drug discontinuation rates were generally low. However, even though RCT captured the most important surrogate endpoints of thrombotic risk and disease progression in PV, they were not statistically powered to fully determine whether therapeutic intervention with ROPEG indeed has a direct positive effect on these important clinical outcomes.

Endometrioid adenocarcinoma arising in adenomyosis in a patient with pelvic organ prolapse-case report

BACKGROUND

Adenomyosis is a frequent finding in endometrial carcinoma patients. Endometrioid adenocarcinoma is the most common type of endometrial carcinoma; however, endometrioid adenocarcinoma arising from adenomyosis is extremely rare.

CASE PRESENTATION

In this case report, we describe a 69-year-old woman who required surgical treatment for pelvic organ prolapse (POP). The patient had been postmenopausal for 20 years and had no abnormal bleeding after menopause. The patient underwent transvaginal hysterectomy, repair of anterior and posterior vaginal walls, ischium fascial fixation and repair of an old perineal laceration. Histological examination of surgical specimens revealed endometrioid adenocarcinoma of the uterus. Bilateral adnexectomy, pelvic lymphadenectomy and para-aortic lymphadenectomy were then performed. The postoperative histopathological diagnosis was stage IB endometrial cancer (endometrioid carcinoma G2).

CONCLUSIONS

In summary, endometrioid adenocarcinoma arising from adenomyosis (EC-AIA) is a rare entity and the early diagnosis is difficult. Adequate preoperative assessment and enhanced inquiry of occult clinical symptoms of postmenopausal women before hysterectomy may contribute to the diagnosis of EC-AIA preoperatively.

Cytological Diagnosis of Classic Myeloproliferative Neoplasms at the Age of Molecular Biology

Myeloproliferative neoplasms (MPN) are clonal hematopoietic stem cell-derived disorders characterized by uncontrolled proliferation of differentiated myeloid cells. Two main groups of MPN, BCR::ABL1-positive (Chronic Myeloid Leukemia) and BCR::ABL1-negative (Polycythemia Vera, Essential Thrombocytosis, Primary Myelofibrosis) are distinguished. For many years, cytomorphologic and histologic features were the only proof of MPN and attempted to distinguish the different entities of the subgroup BCR::ABL1-negative MPN. World Health Organization (WHO) classification of myeloid neoplasms evolves over the years and increasingly considers molecular abnormalities to prove the clonal hematopoiesis. In addition to morphological clues, the detection of JAK2, MPL and CALR mutations are considered driver events belonging to the major diagnostic criteria of BCR::ABL1-negative MPN. This highlights the preponderant place of molecular features in the MPN diagnosis. Moreover, the advent of next-generation sequencing (NGS) allowed the identification of additional somatic mutations involved in clonal hematopoiesis and playing a role in the prognosis of MPN. Nowadays, careful cytomorphology and molecular biology are inseparable and complementary to provide a specific diagnosis and to permit the best follow-up of these diseases.

Myelofibrosis and Survival Prognostic Models: A Journey between Past and Future

Among the myeloproliferative diseases, myelofibrosis is a widely heterogeneous entity characterized by a highly variable prognosis. In this context, several prognostic models have been proposed to categorize these patients appropriately. Identifying who deserves more invasive treatments, such as bone marrow transplantation, is a critical clinical need. Age, complete blood count (above all, hemoglobin value), constitutional symptoms, driver mutations, and blast cells have always represented the milestones of the leading models still used worldwide (IPSS, DIPSS, MYSEC-PM). Recently, the advent of new diagnostic techniques (among all, next-generation sequencing) and the extensive use of JAK inhibitor drugs have allowed the development and validation of new models (MIPSS-70 and version 2.0, GIPSS, RR6), which are continuously updated. Finally, the new frontier of artificial intelligence promises to build models capable of drawing an overall survival perspective for each patient. This review aims to collect and summarize the existing standard prognostic models in myelofibrosis and examine the setting where each of these finds its best application.

Real-world treatments and thrombotic events in polycythemia vera patients in the USA

Polycythemia vera (PV) is a myeloproliferative neoplasm associated with increased risk of thrombotic events (TE) and death. Therapeutic interventions, phlebotomy and cytoreductive medications, are targeted to maintain hematocrit levels < 45% to prevent adverse outcomes. This retrospective observational study examined medical and pharmacy claims of 28,306 PV patients initiating treatment for PV in a data period inclusive of 2011 to 2019. Study inclusion required ≥ 2 PV diagnosis codes in the full data period, at least 1 year of PV treatment history, and ≥ 1 prescription claim and medical claim in both 2018 and 2019. Patients having ≥ 2 hematocrit (HCT) test results in linked outpatient laboratory data (2018-2019) were designated as the HCT subgroup (N = 4246). Patients were characterized as high- or low-risk at treatment initiation based on age and prior thrombotic history. The majority of patients in both risk groups (60% of high-risk and 83% of low-risk) initiated treatment with phlebotomy monotherapy, and during a median follow-up period of 808 days, the vast majority (81% low-risk, 74% high-risk) maintained their original therapy during the follow-up period. Hematocrit control was suboptimal in both risk groups; 54% of high-risk patients initiating with phlebotomy monotherapy sometimes/always had HCT levels > 50%; among low-risk patients, 64% sometimes/always had HCT levels above 50%. Overall, 16% of individuals experienced at least 1 TE subsequent to treatment initiation, 20% (n = 3920) among high-risk and 8% (n = 629) among low-risk patients. This real-world study suggests that currently available PV treatments may not be used to full advantage.

Targeted Next-Generation Sequencing Identifies Additional Mutations Other than BCR∷ABL in Chronic Myeloid Leukemia Patients: A Chinese Monocentric Retrospective Study

A proportion of patients with somatic variants show resistance or intolerance to TKI therapy, indicating additional mutations other than BCR∷ABL1 may lead to TKI treatment failure or disease progression. We retrospectively evaluated 151 CML patients receiving TKI therapy and performed next-generation sequencing (NGS) analysis of 22 CML patients at diagnosis to explore the mutation spectrum other than BCR∷ABL1 affecting the achievement of molecular responses. The most frequently mutated gene was ASXL1 (40.9%). NOTCH3 and RELN mutations were only carried by subjects failing to achieve a major molecular response (MMR) at 12 months. The distribution frequency of ASXL1 mutations was higher in the group that did not achieve MR4.0 at 36 months (p = 0.023). The achievement of MR4.5 at 12 months was adversely impacted by the presence of >2 gene mutations (p = 0.024). In the analysis of clinical characteristics, hemoglobin concentration (HB) and MMR were independent factors for deep molecular response (DMR), and initial 2GTKI therapy was better than 1GTKI in the achievement of molecular response. For the scoring system, we found the ELTS score was the best for predicting the efficacy of TKI therapy and the Socal score was the best for predicting mutations other than BCR∷ABL.