Incidence, clinical features, and prognostic impact of CALR exon 9 mutations in essential thrombocythemia and primary myelofibrosis: an experience of a single tertiary hospital in Korea.
We evaluated the incidence, clinical characteristics, and prognostic impact of calreticulin (CALR) mutations in essential thrombocythemia (ET) and primary myelofibrosis (PMF) patients. In all, 48 ET and 14 PMF patients were enrolled, and the presence of CALR mutations was analyzed by direct sequencing. Patients were classified into three subgroups according to Janus kinase 2 (JAK2) V617F and CALR mutation status, and their clinical features and prognosis were compared. CALR mutations were detected in 15 (24.2%) patients, and the incidence increased to 50.0% in 30 JAK2 V617F mutation-negative cases. These included 11 patients with three known mutations (c.1092_1143del [seven cases], c.1154_1155insTTGTC [three cases], and c.1102_1135del [one case]) and 4 patients with novel mutations. ET patients carrying CALR mutation were younger, had lower white blood cell counts, and experienced less thrombosis during follow-up than those carrying JAK2 V617F mutation, while both patient groups showed similar clinical features and prognosis. In ET patients without JAK2 V617F mutation, CALR mutation did not significantly affect clinical manifestation and prognosis. In conclusion, CALR mutation analysis could be a useful diagnostic tool for ET and PMF in 50% of the cases without JAK2 V617F mutations. The prognostic impact of CALR mutations needs further investigation.
Department of Laboratory Medicine, Pusan National University School of Medicine, Pusan National University Hospital, Busan, Korea. ; Biomedical Research Institute, Pusan National University Hospital, Busan, Korea.
Sang Hyuk
SH
Park
Department of Laboratory Medicine, Pusan National University School of Medicine, Pusan National University Hospital, Busan, Korea. ; Biomedical Research Institute, Pusan National University Hospital, Busan, Korea.
Shine Young
SY
Kim
Department of Laboratory Medicine, Pusan National University School of Medicine, Pusan National University Yangsan Hospital, Yangsan, Korea.
Sun Min
SM
Lee
Department of Laboratory Medicine, Pusan National University School of Medicine, Pusan National University Hospital, Busan, Korea. ; Biomedical Research Institute, Pusan National University Hospital, Busan, Korea.
Jongyoun
J
Yi
Department of Laboratory Medicine, Pusan National University School of Medicine, Pusan National University Yangsan Hospital, Yangsan, Korea.
In-Suk
IS
Kim
Department of Laboratory Medicine, Pusan National University School of Medicine, Pusan National University Hospital, Busan, Korea. ; Biomedical Research Institute, Pusan National University Hospital, Busan, Korea.
Hyung Hoi
HH
Kim
Department of Laboratory Medicine, Pusan National University School of Medicine, Pusan National University Yangsan Hospital, Yangsan, Korea.
Chulhun Ludgerus
CL
Chang
Department of Laboratory Medicine, Pusan National University School of Medicine, Pusan National University Hospital, Busan, Korea. ; Biomedical Research Institute, Pusan National University Hospital, Busan, Korea.
Eun Yup
EY
Lee
Biomedical Research Institute, Pusan National University Hospital, Busan, Korea. ; Division of Hematology-Oncology, Department of Internal Medicine, Pusan National University School of Medicine, Pusan National University Hospital, Busan, Korea.
Moo-Kon
MK
Song
Biomedical Research Institute, Pusan National University Hospital, Busan, Korea. ; Division of Hematology-Oncology, Department of Internal Medicine, Pusan National University School of Medicine, Pusan National University Hospital, Busan, Korea.
Ho-Jin
HJ
Shin
Biomedical Research Institute, Pusan National University Hospital, Busan, Korea. ; Division of Hematology-Oncology, Department of Internal Medicine, Pusan National University School of Medicine, Pusan National University Hospital, Busan, Korea.
Joo Seop
JS
Chung
D000328:Adult; D000368:Aged; D037282:Calreticulin / Q000235:genetics*; D004252:DNA Mutational Analysis; D005091:Exons; D005260:Female; D005838:Genotype; D006801:Humans; D054643:INDEL Mutation; D053614:Janus Kinase 2 / Q000235:genetics; D008297:Male; D008875:Middle Aged; D055728:Primary Myelofibrosis / Q000175:diagnosis / Q000453:epidemiology / Q000235:genetics*; D011379:Prognosis; D056910:Republic of Korea; D062606:Tertiary Care Centers; D013920:Thrombocythemia, Essential / Q000175:diagnosis / Q000453:epidemiology / Q000235:genetics*; D055815:Young Adult
C576483:CALR protein, human; D037282:Calreticulin; D053614:Janus Kinase 2
CALR; Clinical feature; Essential thrombocythemia; Incidence; Mutation; Primary myelofibrosis; Prognosis