The BCR/ABL fusion gene or the Ph^1-chromosome in the t(9;22)(q34;q11)exerts a high tyrokinase acticity,which is the cause of chronic myeloid leukemia(CML).The1990 Hannover Bone Marrow Classification separated CML fro...The BCR/ABL fusion gene or the Ph^1-chromosome in the t(9;22)(q34;q11)exerts a high tyrokinase acticity,which is the cause of chronic myeloid leukemia(CML).The1990 Hannover Bone Marrow Classification separated CML from the myeloproliferative disorders essential thrombocythemia(ET),polycythemia vera(PV)and chronic megakaryocytic granulocytic myeloproliferation(CMGM).The 2006-2008 European Clinical Molecular and Pathological(ECMP)criteria discovered 3variants of thrombocythemia:ET with features of PV(prodromal PV),"true"ET and ET associated with CMGM.The 2008 World Health Organization(WHO)-ECMP and 2014 WHO-CMP classifications defined three phenotypes of JAK2^(V617F)mutated ET:normocellular ET(WHO-ET),hypercelluar ET due to increased erythropoiesis(prodromal PV)and ET with hypercellular megakaryocytic-granulocytic myeloproliferation.The JAK2^(V617F)mutation load in heterozygous WHO-ET is low and associated with normal life expectance.The hetero/homozygous JAK2^(V617F)mutation load in PV and myelofibrosis is related to myeloproliferative neoplasm(MPN)disease burden in terms of symptomaticsplenomegaly,constitutional symptoms,bone marrow hypercellularity and myelofibrosis.JAK2 exon 12mutated MPN presents as idiopathic eryhrocythemia and early stage PV.According to 2014 WHO-CMP criteria JAK2 wild type MPL^(515)mutated ET is the second distinct thrombocythemia featured by clustered giant megakaryocytes with hyperlobulated stag-horn-like nuclei,in a normocellular bone marrow consistent with the diagnosis of"true"ET.JAK2/MPL wild type,calreticulin mutated hypercellular ET appears to be the third distinct thrombocythemia characterized by clustered larged immature dysmorphic megakaryocytes and bulky(bulbous)hyperchromatic nuclei consistent with CMGM or primary megakaryocytic granulocytic myeloproliferation.展开更多
The Polycythemia Vera Study Group(PVSG),World Health Organization(WHO) and European Clinical,Molecular and Pathological(ECMP) classifications agree upon the diagnostic criteria for polycythemia vera(PV) and advanced p...The Polycythemia Vera Study Group(PVSG),World Health Organization(WHO) and European Clinical,Molecular and Pathological(ECMP) classifications agree upon the diagnostic criteria for polycythemia vera(PV) and advanced primary myelofibrosis(MF). Essential thrombocythemia(ET) according to PVSG and 2007/2008 WHO criteria comprises three variants of JAK2V617 F mutated ET when the ECMP criteria are applied. These include normocellular ET,hypercellular ET with features of early PV(prodromal PV),and hypercellular ET due to megakaryocytic,granulocytic myeloprolifera-tion(ET.MGM). Evolution of prodromal PV into overt PV is common. Development of MF is rare in normocellular ET(WHO-ET) but rather common in hypercellular ET.MGM. The JAK2V617 F mutation burden in heterozygous mutated normocellular ET and in heterozygous/homozygous or homozygous mutated PV and ET.MGM is of major prognostic significance. JAK2/MPL wild type ET associated with prefibrotic primary megakaryocytic and granulocytic myeloproliferation(PMGM) is characterized by densely clustered immature dysmorphic megakaryocytes with bulky(bulbous) hyperchromatic nuclei,which are never seen in JAK2V617 F mutated ET,and PV and also not in MPL515 mutated normocellular ET(WHO-ET). JAK2V617 mutation burden,spleen size,LDH,circulating CD34+ cells,and pre-treatment bone marrow histopathology are mandatory to stage the myeloproliferative neoplasms ET,PV,PMGM for proper prognosis assessment and therapeutic implications. MF itself is not a disease because reticulin fibrosis and reticulin/collagen fibrosis are secondary responses of activated polyclonal fibroblasts to cytokines released from the clonal myeloproliferative granulocytic and megakaryocytic progenitor cells in ET.MGM,PV and PMGM.展开更多
文摘The BCR/ABL fusion gene or the Ph^1-chromosome in the t(9;22)(q34;q11)exerts a high tyrokinase acticity,which is the cause of chronic myeloid leukemia(CML).The1990 Hannover Bone Marrow Classification separated CML from the myeloproliferative disorders essential thrombocythemia(ET),polycythemia vera(PV)and chronic megakaryocytic granulocytic myeloproliferation(CMGM).The 2006-2008 European Clinical Molecular and Pathological(ECMP)criteria discovered 3variants of thrombocythemia:ET with features of PV(prodromal PV),"true"ET and ET associated with CMGM.The 2008 World Health Organization(WHO)-ECMP and 2014 WHO-CMP classifications defined three phenotypes of JAK2^(V617F)mutated ET:normocellular ET(WHO-ET),hypercelluar ET due to increased erythropoiesis(prodromal PV)and ET with hypercellular megakaryocytic-granulocytic myeloproliferation.The JAK2^(V617F)mutation load in heterozygous WHO-ET is low and associated with normal life expectance.The hetero/homozygous JAK2^(V617F)mutation load in PV and myelofibrosis is related to myeloproliferative neoplasm(MPN)disease burden in terms of symptomaticsplenomegaly,constitutional symptoms,bone marrow hypercellularity and myelofibrosis.JAK2 exon 12mutated MPN presents as idiopathic eryhrocythemia and early stage PV.According to 2014 WHO-CMP criteria JAK2 wild type MPL^(515)mutated ET is the second distinct thrombocythemia featured by clustered giant megakaryocytes with hyperlobulated stag-horn-like nuclei,in a normocellular bone marrow consistent with the diagnosis of"true"ET.JAK2/MPL wild type,calreticulin mutated hypercellular ET appears to be the third distinct thrombocythemia characterized by clustered larged immature dysmorphic megakaryocytes and bulky(bulbous)hyperchromatic nuclei consistent with CMGM or primary megakaryocytic granulocytic myeloproliferation.
文摘The Polycythemia Vera Study Group(PVSG),World Health Organization(WHO) and European Clinical,Molecular and Pathological(ECMP) classifications agree upon the diagnostic criteria for polycythemia vera(PV) and advanced primary myelofibrosis(MF). Essential thrombocythemia(ET) according to PVSG and 2007/2008 WHO criteria comprises three variants of JAK2V617 F mutated ET when the ECMP criteria are applied. These include normocellular ET,hypercellular ET with features of early PV(prodromal PV),and hypercellular ET due to megakaryocytic,granulocytic myeloprolifera-tion(ET.MGM). Evolution of prodromal PV into overt PV is common. Development of MF is rare in normocellular ET(WHO-ET) but rather common in hypercellular ET.MGM. The JAK2V617 F mutation burden in heterozygous mutated normocellular ET and in heterozygous/homozygous or homozygous mutated PV and ET.MGM is of major prognostic significance. JAK2/MPL wild type ET associated with prefibrotic primary megakaryocytic and granulocytic myeloproliferation(PMGM) is characterized by densely clustered immature dysmorphic megakaryocytes with bulky(bulbous) hyperchromatic nuclei,which are never seen in JAK2V617 F mutated ET,and PV and also not in MPL515 mutated normocellular ET(WHO-ET). JAK2V617 mutation burden,spleen size,LDH,circulating CD34+ cells,and pre-treatment bone marrow histopathology are mandatory to stage the myeloproliferative neoplasms ET,PV,PMGM for proper prognosis assessment and therapeutic implications. MF itself is not a disease because reticulin fibrosis and reticulin/collagen fibrosis are secondary responses of activated polyclonal fibroblasts to cytokines released from the clonal myeloproliferative granulocytic and megakaryocytic progenitor cells in ET.MGM,PV and PMGM.
