Essential Thrombocythemia in Children and Adolescents
Open Access
Abstract
This paper reviews the features of pediatric essential thrombocythemia (ET). ET is a rare disease in children, challenging pediatric and adult hematologists alike. The current WHO classification acknowledges classical Philadelphia-negative MPNs and defines diagnostic criteria, mainly encompassing adult cases. The presence of one of three driver mutations (JAK2V617F, CALR, and MPL mutations) represent the proof of clonality typical of ET. Pediatric ET cases are thus usually confronted by adult approaches. These can fit only some patients, because only 25–40% of cases present one of the driver mutations. The diagnosis of hereditary, familial thrombocytosis and the exclusion of reactive/secondary thrombocytosis must be part of the diagnostic process in children and can clarify most of the negative cases. Still, many children present a clinical, histological picture of ET, with a molecular triple wild-type status. Moreover, prognosis seems more benign, at least within the first few decades of follow-up. Thrombotic events are rare, and only minor hemorrhages are ordinarily observed. As per the management, the need to control symptoms must be balanced with the collateral effects of lifelong drug therapy. We conclude that these differences concert a compelling case for a very careful therapeutic approach and advocate for the importance of further cooperative studies.Keywords
This publication has 104 references indexed in Scilit:
- Anagrelide compared with hydroxyurea in WHO-classified essential thrombocythemia: the ANAHYDRET Study, a randomized controlled trialBlood, 2013
- Age- And Sex-Related Variations in Platelet Count in Italy: A Proposal of Reference Ranges Based on 40987 Subjects' DataPLOS ONE, 2013
- Effect of Iron Therapy on Platelet Counts in Patients with Inflammatory Bowel Disease-Associated AnemiaPLOS ONE, 2012
- Thrombocythemia and polycythemia in patients younger than 20 years at diagnosis: clinical and biologic features, treatment, and long-term outcomeBlood, 2012
- Thrombocytosis: Diagnostic Evaluation, Thrombotic Risk Stratification, and Risk-Based Management StrategiesThrombosis, 2011
- Hereditary thrombocytosis caused by MPLSer505Asn is associated with a high thrombotic risk, splenomegaly and progression to bone marrow fibrosisHaematologica, 2009
- Evidence for a founder effect of the MPL-S505N mutation in eight Italian pedigrees with hereditary thrombocythemiaHaematologica, 2009
- MPLW515L Is a Novel Somatic Activating Mutation in Myelofibrosis with Myeloid MetaplasiaPLOS Medicine, 2006
- Hydroxyurea Compared with Anagrelide in High-Risk Essential ThrombocythemiaNew England Journal of Medicine, 2005
- A unique clonal JAK2 mutation leading to constitutive signalling causes polycythaemia veraNature, 2005