Mutational profile and cardiovascular risk factors impact prognosis in triple-negative essential thrombocythemia.
Key claim: In triple-negative essential thrombocythemia, pathogenic non-driver mutations (notably ASXL1, CBL, EZH2, and ZRSR2) predict leukemic progression and worse overall survival, while age over 60, prior thrombosis, and cardiovascular risk factors drive thrombotic risk.
Abstract
Triple-negative essential thrombocythemia (TN-ET) represents a diagnostic and therapeutic challenge. The aim of the present study was to identify prognostic factors useful for tailoring treatment. 241 TN-ET patients with myeloid panel sequencing and confirmatory bone marrow biopsy were selected. Pathogenic/likely pathogenic variants were identified in 19.5% of patients. Mutation carriers were older (median age 66 years vs. 53, p < 0.001) and had a higher frequency of prior thrombosis (19.6% vs. 6.5%, p = 0.013). Presence of pathogenic/likely pathogenic variants was associated with leukemic progression (HR 12.608; 95% CI: 2.616-60.775, p = 0.002) and lower overall survival (HR 3.008; 95% CI: 1.43-6.327, p = 0.004). ASXL1 (p = 0.004), CBL (p < 0.001), EZH2 (p < 0.001), and ZRSR2 (p < 0.001) mutations were associated with inferior leukemia-free survival. Age over 60 years, previous thrombosis, and cardiovascular risk factors were associated with higher thrombotic risk. Revised IPSET-thrombosis was useful for risk stratification (10-year probability of overall thrombosis: 30%, 15%, and 6% for high-, intermediate-, and very-low risk patients, respectively, p < 0.001). ARTS score refined arterial thrombosis stratification (10 years probability: 25% and 6% for high- and low-risk, respectively, p < 0.001). Progression to myelofibrosis was a rare event in this cohort (2.5%). These results highlight the biological and prognostic relevance of molecular profile in TN-ET.
Why this matters
Triple-negative ET (~10% of ET) lacks the JAK2/CALR/MPL anchors used for standard risk stratification, leaving prognostication uncertain. This finding shows that classical clinical thrombosis predictors (age >60, prior thrombosis, cardiovascular risk factors, IPSET-thrombosis, ARTS) still apply, while non-driver mutations — particularly ASXL1, CBL, EZH2, and ZRSR2 — carry the leukemic-progression and survival signal, providing an actionable molecular framework for a subset that has been prognostically orphaned.