Contributions
Abstract: PB2307
Type: Publication Only
Background
Myeloproliferative neoplasms (MPN) are the group of clonal, malignant hematopoietic stem cell disorders, characterized by the proliferation of one or more blood lines with normal or nearly normal maturing in the bone marrow and in extramedullar hematopoietic organs. The following factors give contribution to the incidence of thrombosis: increasing level of products that are formed in the activation of platelets (thromboxane, p-selectin); increased production of microparticles that are parts of various cell membrane structures of platelet origin; JAK2V617F mutation. In patients with MPN there is increased activity of the coagulation system due to the resistance to the anticoagulant function of thrombomodulin.
Aims
The aim of this study is to monitor JAK2V617F mutation as a potential risk factor for the incidence of thrombotic complications in patients with Philadelphia negative myeloproliferative neoplasms
Methods
During the six-year period we monitored the occurrence of thrombotic complications in 157 patients of both sexes, aged between 30 and 87 years, being diagnosed with Ph-myeloproliferative neoplasm. Patients were classified into the following groups: 1. Group with polycythemia vera (PV) (68); 2. Group with essential thrombocythemia (ET) (36); 3. Group with idiopathic myelofibrosis (IMF) (26); 4. Group with unclassified myeloproliferative neoplasm (MPNs) (27). Among possible risk factors, we monitored the presence of JAK2V617F mutation, as well as the age of patients, deviations in counts of leukocytes, the presence of cardiovascular comorbidity, and the presence of diabetes mellitus. We used methods of clinical, laboratory, endoscopy, ultrasound and CT scans.
Results
JAK2V617F mutation was statistically more significantly present in patients with PV (about 81%). In patients with ET it was noticed 58%, in patients with IMF about 38%, and in group of patients with MPNs about 48%. The highest percentage of thrombotic complications (arterial and venous) was found in the group of patients with ET, which was statistically more significant relative to PV. Thrombotic complications were in both groups more frequent in percentage with JAK2V617F positive patients, but without statistical significance. It is believed that activated neutrophils bind to platelets by influencing the increased expression of tissue factor activity, as well as the activation and damage of the endothelial cells, especially with JAK2V617F positive patients. In patients with IMF, thrombotic complications were statistically more significantly present in JAK2V617F positive patients. In patients with MPNs, thrombotic complications were more common in JAK2V617F positive patients, but with significant deviations reported in the count of leukocytes in terms of leukocytosis. Thrombotic complications in all groups, except in the IMF group, were more commonly present in patients with cardiovascular comorbidity and diabetes mellitus, but the statistical significance was present only in the group with PV and ET.
Conclusion
JAK2V617F mutation can be considered as potential risk factors for thrombosis in patients with Philadelphia negative myeloproliferative disorders. Other risk factors must be also considered, like leukocytosis populations, cardiovascular diseases and diabetes mellitus. Further monitoring of those patients and a larger number of subjects is needed.
Session topic: 16. Myeloproliferative neoplasms - Clinical
Keyword(s): Essential Thrombocytemia, Myelofibrosis, Myeloproliferative disorder, Polycythemia vera
Abstract: PB2307
Type: Publication Only
Background
Myeloproliferative neoplasms (MPN) are the group of clonal, malignant hematopoietic stem cell disorders, characterized by the proliferation of one or more blood lines with normal or nearly normal maturing in the bone marrow and in extramedullar hematopoietic organs. The following factors give contribution to the incidence of thrombosis: increasing level of products that are formed in the activation of platelets (thromboxane, p-selectin); increased production of microparticles that are parts of various cell membrane structures of platelet origin; JAK2V617F mutation. In patients with MPN there is increased activity of the coagulation system due to the resistance to the anticoagulant function of thrombomodulin.
Aims
The aim of this study is to monitor JAK2V617F mutation as a potential risk factor for the incidence of thrombotic complications in patients with Philadelphia negative myeloproliferative neoplasms
Methods
During the six-year period we monitored the occurrence of thrombotic complications in 157 patients of both sexes, aged between 30 and 87 years, being diagnosed with Ph-myeloproliferative neoplasm. Patients were classified into the following groups: 1. Group with polycythemia vera (PV) (68); 2. Group with essential thrombocythemia (ET) (36); 3. Group with idiopathic myelofibrosis (IMF) (26); 4. Group with unclassified myeloproliferative neoplasm (MPNs) (27). Among possible risk factors, we monitored the presence of JAK2V617F mutation, as well as the age of patients, deviations in counts of leukocytes, the presence of cardiovascular comorbidity, and the presence of diabetes mellitus. We used methods of clinical, laboratory, endoscopy, ultrasound and CT scans.
Results
JAK2V617F mutation was statistically more significantly present in patients with PV (about 81%). In patients with ET it was noticed 58%, in patients with IMF about 38%, and in group of patients with MPNs about 48%. The highest percentage of thrombotic complications (arterial and venous) was found in the group of patients with ET, which was statistically more significant relative to PV. Thrombotic complications were in both groups more frequent in percentage with JAK2V617F positive patients, but without statistical significance. It is believed that activated neutrophils bind to platelets by influencing the increased expression of tissue factor activity, as well as the activation and damage of the endothelial cells, especially with JAK2V617F positive patients. In patients with IMF, thrombotic complications were statistically more significantly present in JAK2V617F positive patients. In patients with MPNs, thrombotic complications were more common in JAK2V617F positive patients, but with significant deviations reported in the count of leukocytes in terms of leukocytosis. Thrombotic complications in all groups, except in the IMF group, were more commonly present in patients with cardiovascular comorbidity and diabetes mellitus, but the statistical significance was present only in the group with PV and ET.
Conclusion
JAK2V617F mutation can be considered as potential risk factors for thrombosis in patients with Philadelphia negative myeloproliferative disorders. Other risk factors must be also considered, like leukocytosis populations, cardiovascular diseases and diabetes mellitus. Further monitoring of those patients and a larger number of subjects is needed.
Session topic: 16. Myeloproliferative neoplasms - Clinical
Keyword(s): Essential Thrombocytemia, Myelofibrosis, Myeloproliferative disorder, Polycythemia vera