Non‐Invasive Stratification of Portal Hypertension in Patients With BCR :: ABL1 ‐Negative Myeloproliferative Neoplasms

ABSTRACT Background & Aims The course of BCR::ABL1‐negative myeloproliferative neoplasms (MPN) is frequently complicated by thromboembolic events in the splanchnic venous system, resulting in portal hypertension (PH). Therefore, the introduction of spleen stiffness measurement (SSM) might improve the diagnosis of PH. The aim of this study was to evaluate the clinical utility of SSM (performed by using the 100 Hz probe) in non‐invasive stratification of PH in these patients. Methods We performed a retrospective, monocentric, cross‐sectional analysis including consecutive patients with BCR::ABL1‐negative MPN attending the haematological outpatient clinic at the Medical University of Vienna with available liver stiffness (LSM)/SSM from 10/2023 to 09/2024. LSM/SSM were linked to signs and events of PH. Results Fifty‐five patients were included (mean age 57.9 ± 14.2 years, 69% females, polycythaemia vera as main entity). One fourth of patients had splanchnic vein thrombi. Nineteen patients (34.5%) had specific and 29 patients (52.7%) had unspecific signs of PH. Twelve patients (21.8%) experienced PH events prior to study inclusion. SSM correlated with disease severity (i.e., JAK2 V617F allele frequency). LSM/SSM adequately stratified patients with vs. without PH. While SSM was strongly linked with splenomegaly, it yielded independent information regarding PH on top of splenomegaly. The implementation of sequential LSM (< 5 & ≥ 15 kPa) and SSM (< 21 & ≥ 50 kPa) for ruling in and out PH reduced the grey zone (24%) with adequate sensitivity/specificity. Conclusions While SSM is strongly correlated with splenomegaly and disease severity, it is independently associated with PH in patients with BCR::ABL1‐negative MPN. Implementation of LSM/SSM might improve patient management.