Liver and Spleen Point Shear-Wave Elastography in Newly Diagnosed BCR-ABL1-Negative Myeloproliferative Neoplasms: Associations with Hematologic Parameters and Bone Marrow Fibrosis Grade - A Prospective Cross-Sectional Study

Objective: To quantify liver and spleen stiffness at diagnosis in treatment-naive BCR::ABL1-negative myeloproliferative neoplasms (MPNs) using point shear-wave elastography (pSWE), and to explore associations with hematologic parameters and bone marrow fibrosis grade. Materials and Methods: Prospective pSWE was performed in 33 treatment-naive patients with BCR::ABL1-negative MPNs (essential thrombocythemia [ET] n=13, primary myelofibrosis [PMF] n=12, polycythemia vera [PV] n=8) and 31 age- and sex-matched controls. Shear-wave velocity (Vs, m/s) was recorded as the median of ≥10 valid measurements per organ, with interquartile range/median <30% as the reliability criterion. Correlations with blood counts and bone marrow fibrosis grade were evaluated. ROC analysis was exploratory because of the modest sample size and limited high-grade fibrosis cases. Results: Hepatic Vs was higher in patients than controls (1.21 [1.09-1.34] vs 0.98 [0.86-1.11] m/s; p<0.01), whereas splenic Vs was similar (3.09 [2.76-3.50] vs 3.21 [2.91-3.44] m/s; p=0.41). Hepatic Vs correlated with leukocyte count (r=0.47; p<0.01) and bone marrow fibrosis grade (r=0.47; p<0.05). Hepatic Vs identified MF grade 3 with an AUC of 0.77; however, the proposed cut-off of ≥1.22 m/s should be interpreted as a preliminary research threshold rather than a clinically validated decision point. Conclusion: At diagnosis, hepatic stiffness is increased in this treatment-naive BCR::ABL1-negative MPN cohort and shows a modest association with marrow fibrosis grade and leukocyte count. Splenic stiffness is not increased in this mixed-subtype cohort. These findings support hepatic pSWE as a hypothesis-generating adjunct to baseline phenotyping, not a replacement for bone marrow biopsy or hematologic risk assessment.