From the Guidelines
Essential thrombocythemia (ET) is a chronic condition characterized by persistently elevated platelet counts, and its management should prioritize reducing the risk of thrombotic events and improving quality of life, with low-dose aspirin and cytoreductive therapy being cornerstone treatments. The symptoms of ET include headaches, dizziness, visual disturbances, erythromelalgia, and an increased risk of thrombotic events and bleeding 1. Management depends on risk stratification, with low-risk patients typically receiving low-dose aspirin (81-100mg daily) to prevent clotting complications, while high-risk patients require cytoreductive therapy, with hydroxyurea being first-line (starting at 500-1000mg daily, adjusted to maintain platelets below 400,000/μL) 1.
Key Considerations in ET Management
- Risk stratification is crucial, with age and history of thrombosis being key factors in determining the risk category 1.
- Low-dose aspirin is recommended for low-risk patients to prevent clotting complications, but its use should be cautious in patients with acquired von Willebrand disease 1.
- Hydroxyurea is the first-line cytoreductive therapy for high-risk patients, with interferon-alpha, anagrelide, and ruxolitinib being alternative options for specific cases or refractory disease 1.
- Regular monitoring of blood counts and addressing cardiovascular risk factors like hypertension, diabetes, and smoking are essential for managing ET and improving patient outcomes 1.
Monitoring and Follow-Up
- Monitoring for new thrombosis, acquired von Willebrand disease, and disease-related major bleeding, as well as managing cardiovascular risk factors, is recommended for all patients 1.
- The development of new thrombosis, disease-related major bleeding, or signs of disease progression are indications for cytoreductive therapy or adjustment of current treatment 1.
Treatment Goals
- The primary goal of ET treatment is to reduce the risk of thrombotic events and improve quality of life, with a focus on minimizing treatment-related toxicity and maximizing patient outcomes 1.
- Hydroxyurea, as the first-line cytoreductive therapy, aims to maintain platelet counts below 400,000/μL, thereby reducing the risk of thrombotic complications 1.
From the Research
Essential Thrombocythemia Symptoms
- Essential thrombocythemia (ET) is a clonal myeloproliferative neoplasm with excessive platelet production, associated with an increased risk of thrombosis and bleeding 2
- Patients with ET have a persistent platelet count of 450 × 109/L or greater 2
- The differential diagnosis includes myeloproliferative neoplasms, inflammatory conditions, infections, splenectomy, iron deficiency anemia, and solid tumors 2
- Approximately 90% of individuals with ET have genetic variants that upregulate the JAK-STAT signaling pathway, including Janus kinase 2 (JAK2), calreticulin (CALR), and myeloproliferative leukemia virus oncogene (MPL) 2
Management of Essential Thrombocythemia
- Use of aspirin (81-100 mg/d) is suggested for most patients with ET to lower thrombosis risk 2, 3
- Cytoreduction with hydroxyurea significantly lowered the risk of arterial or venous thrombotic events compared with no cytoreductive therapy in high-risk patients 4, 2
- Low-dose aspirin once daily is the recommended treatment for the control of vascular events in all ET risk categories, except patients at very low risk 3
- Twice daily aspirin administration may be considered to overcome the problem of inadequate inhibition of platelet TxA2 production with once daily regimen 3
Risk Factors and Complications
- Thrombosis risk is increased among those with a history of thrombosis, age older than 60 years, a JAK2 gene variant, and cardiovascular risk factors 2
- Patients with ET are at increased risk of arterial thrombosis, venous thrombosis, and hemorrhagic complications 2
- Approximately 10% of patients with ET develop myelofibrosis and about 3% develop acute myeloid leukemia at a median of 8.5 years from diagnosis 2