The treatment of essential thromobocytosis revisited

Pathological and genomic features of myeloproliferative neoplasms associated with splanchnic vein thrombosis in a single-center cohort

Here, we reviewed clinical-morphological data and investigated mutational profiles by NGS in a single-center series of 58 consecutive MPN-SVT patients admitted to our hospital between January 1979 and November 2021. We identified 15.5% of PV, 13.8% of ET, 34.5% of PMF, 8.6% of SMF and 27.6% of MPN-U. Most cases (84.5%) carried JAK2V617F mutation, while seven patients were characterized by other molecular markers, namely MPL in four and CALR mutations in three cases. NGS was performed in 54 (93.1%) cases: the most frequent additional mutations were found in TET2 (27.8%) and DNMT3A (16.7%) genes, whereas 25 (46.3%) patients had no additional mutation. Cases with JAK2V617F homozygosity had a higher median number of additional mutations than those with low allele burden. More importantly, all cases of leukemic evolution were characterized by a higher median number of co-mutations, and a co-mutational pattern of high-risk lesions, such as truncating mutations of ASXL1, bi-allelic TP53 loss, and CSMD1 mutations. Nevertheless, no difference was found between cases with and without additional somatic mutations regarding fibrotic progression, SVT recurrence, other thrombo-hemorrhagic complications, or death. After a median follow-up of 7.1 years, ten deaths were recorded; fibrotic progression/leukemic evolution was ascertained in one (1.7%) and six (10.3%) patients, respectively, while 22 (37.9%) patients suffered from recurrent thrombosis. In conclusion, our data underline the importance of using NGS analysis in the management of MPN-related SVT as it can support the MPN diagnosis, particularly in "triple-negative" cases, and provide additional information with potential consequences on prognosis and therapeutic strategies.

Optimal therapy for polycythemia vera and essential thrombocythemia: Preferred use of interferon therapy based on phase 2 trials

OBJECTIVES

To determine the value of recombinant interferon-alfa (rIFNα) in the treatment of polycythemia vera (PV) and essential thrombocythemia (ET) based on its biological activities and phase 2 clinical studies, pending completion of phase 3 trials; to determine importance of the Internet in patient decision-making in treatment selection.

RESULTS

The value of rIFNα in PV and ET is based upon its biological effects on PV stem cells and megakaryocyte proliferation. Single-arm trials are useful for life-threatening diseases when there are relatively few patients to evaluate endpoints, such as rIFNα treatment of PV and ET. Proper diagnostic criteria are mandatory; for PV, the current World Health Organization criteria emphasizing increased hemoglobin values exclude approximately one-third of eligible patients. Importance of these data: Single-arm studies in diseases exemplified by rIFNα in PV require updated diagnostic criteria for research and for clinical practice. The influence of the Internet on patient decisions for treatment is noteworthy.

CONCLUSION

The biologic basis for selecting therapy is exemplified by rIFNα in treating PV and ET. Current single-arm studies of rIFNα in PV and ET are relevant and acceptable. The importance of the Internet in patient decision-making is important.

Discrepancies between bone marrow histopathology and clinical phenotype in BCR-ABL1-negative myeloproliferative neoplasms associated with splanchnic vein thrombosis

We examined a consecutive series of 29 patients with myeloproliferative neoplasms (MPNs) associated with splanchnic vein thrombosis (SVT) in order to evaluate their bone marrow morphology and identify possible associations between histological findings and clinical features. Eleven patients showed the morphological features of polycythemia vera (PV), 11 of primary myelofibrosis (PMF) and six of essential thrombocythemia (ET). Molecular analyses identified the JAK2 V617F mutation in 27 patients; one of the JAK2-negative patients carried the MPL W515K mutation, the other was "triple-negative" (no JAK2, MPL or CALR mutation). On the basis of the WHO classification, three patients were classified as having PV, 11 as having PMF, and two as having ET; the remaining 13 cases fell into the MPN-unclassifiable category as there were discrepancies between their morphological and clinical features. In conclusion, our findings suggest that bone marrow histology should always be considered a key component of the diagnostic algorithm in patients with SVT, but that it is not enough to distinguish the different entities. This is particularly important because diagnoses of PV, PMF or ET have very different prognoses and obviously imply different therapies. It is therefore necessary to adopt a comprehensive approach that considers morphological, clinical and molecular data.

Essential thrombocythemia: a rare disease in childhood

Essential thrombocythemia is an acquired myeloproliferative disorder characterized by the proliferation of megakaryocytes in bone marrow, leading to a persistent increase in the number of circulating platelets and thus increasing the risk for thrombotic and hemorrhagic events. The disease features leukocytosis, splenomegaly, vascular occlusive events, hemorrhages and vasomotor disorders. The intricate mechanisms underlying the molecular pathogenesis of this disorder are not completely understood and are still a matter of discussion. Essential thrombocythemia is an extremely rare disorder during childhood. We report on a case of essential thrombocythemia in a child and discuss the diagnostic approach and treatment strategy.