From the Research
Essential thrombocytosis (ET) has an estimated prevalence of approximately 38 to 57 cases per 100,000 people in the general population, with an incidence rate of 0.2 to 2.5 per 100,000 people per year. The condition is characterized by the overproduction of platelets in the bone marrow, resulting in elevated platelet counts in the peripheral blood. ET is caused by acquired mutations, most commonly in the JAK2, CALR, or MPL genes, which lead to dysregulated platelet production 1. The prevalence may be underestimated as many patients are asymptomatic and diagnosed incidentally during routine blood tests.
Key Characteristics of ET
- The condition typically affects middle-aged to older adults, with a median age at diagnosis of around 60 years, though it can occur at any age, including in children and young adults.
- There is a slight female predominance, with women being affected about 1.5 to 2 times more frequently than men.
- The spectrum of symptoms is quite wide, but fatigue results to be the most frequent.
- Thrombosis is frequently observed, often occurring before or at the time of diagnosis.
Diagnosis and Treatment
- The criteria for diagnosis were reviewed in 2016 by WHO.
- The classification of thrombotic risk has undergone several revisions, with the revised-IPSET-t distinguishing 4 risk classes, from very low risk to high risk.
- Antiplatelet therapy is recommended in all patients aged ≥ 60 years and in those with a positive history of thrombosis or with cardiovascular risk factors, while cytoreductive therapy with hydroxyurea or interferon is reserved for high-risk patients 1.
- Driver mutations seem to influence thrombotic risk and prognosis, while the role of sub-driver mutations still remains uncertain.
Recent Studies
- A recent study published in 2023 found that pegylated interferon-α (PEG) and hydroxyurea (HU) are both effective treatments for ET, with PEG leading to a greater reduction in JAK2V617F at 24 months, but histopathologic responses were more frequent with HU 2.
- Another study published in 2020 found that the incidence of ET varies from 0.2 to 2.5:100,000 people per year, with a prevalence of 38 to 57 cases per 100,000 people 1.