The association of JAK2V617F mutation and leukocytosis with thrombotic events in essential thrombocythemia.
OBJECTIVE
The Janus kinase 2 mutation, JAK2 (V617F), and megakaryocytic mutations, MPL (W515L/K), have been identified and correlated with a subtype of essential thrombocythemia (ET) patients. We investigated the frequency of mutations in ET patients and analyzed the relationship with their clinical features.


METHODS
Fifty-three ET patients were enrolled in the study. The amplification refractory mutation system was applied for the mutation survey of the JAK2V617F, while the polymerase chain reaction with sequencing was used for the mutation survey of MPLW515L/K.


RESULTS
Thirty-five (66%) patients harboring the JAK2 (V617F) mutation, including 3 homozygous and 32 heterozygous changes, but no MPLW515L/K mutation, were found. During follow-up, 17 (32.1%) patients suffered from documented thrombotic events, with 15 having JAK2V617F mutations. Statistical analysis showed that patients with the JAK2 mutation had significantly higher leukocytes, hemoglobin level, and thrombotic event (p = 0.043, p = 0.001, and p = 0.029, respectively). Thrombotic events were also significantly correlated with leukocytosis and older age.


CONCLUSIONS
The JAK2V617F mutation was noted in a certain population of ET patients and correlated with leukocytosis, high hemoglobin level, and thrombosis. Therefore, detection of the JAK2V617F mutation can affect not only the diagnosis, but also the management of ET patients.
Hsiao
Hui-Hua
HH
Faculty of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan.
Yang
Ming-Yu
MY
Liu
Yi-Chang
YC
Lee
Ching-Ping
CP
Yang
Wen-Chi
WC
Liu
Ta-Chih
TC
Chang
Chao-Sung
CS
Lin
Sheng-Fung
SF
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D004252:DNA Mutational Analysis; D019468:Disease Management; D005260:Female; D005838:Genotype; D006454:Hemoglobins / Q000032:analysis; D006801:Humans; D053614:Janus Kinase 2 / Q000235:genetics*; D007964:Leukocytosis / Q000150:complications*; D008297:Male; D008875:Middle Aged; D009154:Mutation; D012307:Risk Factors; D013920:Thrombocythemia, Essential / Q000150:complications* / Q000235:genetics; D013927:Thrombosis / Q000209:etiology*
D006454:Hemoglobins; D053614:Janus Kinase 2