Exploring the Molecular Aspects of Myeloproliferative Neoplasms Associated with Unusual Site Vein Thrombosis: Review of the Literature and Latest Insights

Abstract

Myeloproliferative neoplasms (MPNs) are the leading causes of unusual site thrombosis, affecting nearly 40% of individuals with conditions like Budd-Chiari syndrome or portal vein thrombosis. Diagnosing MPNs in these cases is challenging because common indicators, such as spleen enlargement and elevated blood cell counts, can be obscured by portal hypertension or bleeding issues. Recent advancements in diagnostic tools have enhanced the accuracy of MPN diagnosis and classification. While bone marrow biopsies remain significant diagnostic criteria, molecular markers now play a pivotal role in both diagnosis and prognosis assessment. Hence, it is essential to initiate the diagnostic process for splanchnic vein thrombosis with a JAK2 V617F mutation screening, but a comprehensive approach is necessary. A multidisciplinary strategy is vital to accurately determine the specific subtype of MPNs, recommend additional tests, and propose the most effective treatment plan. Establishing specialized care pathways for patients with splanchnic vein thrombosis and underlying MPNs is crucial to tailor management approaches that reduce the risk of hematological outcomes and hepatic complications.

Keywords: cerebral vein thrombosis; clonal hematopoiesis of indeterminate potential; myeloproliferative neoplasms; splanchnic vein thrombosis.

Figure 1

Clinical, molecular, and emerging factors that play a pivotal role in the pathogenesis of MPNs associated with SVT. In detail, risk factors related to MPN are highlighted in red; risk factors associated with patient characteristics are indicated in orange; portal-flow-related risk factors are presented in blue; and emerging factors are depicted in purple.

Figure 2

Diagnostic evaluation for myeloproliferative neoplasms (MPNs) associated with splanchnic vein thrombosis (SVT). BM: bone marrow; CALR: calreticulin, ET: essential thrombocythemia, JAK2: janus kinase 2; MPL: myeloproliferative leukemia virus oncogene; NGS: next-generation sequencing, PLT: platelets; PMF: primary myelofibrosis; PV: polycythemia vera.