Abstract
Background: Non chronic myelogenous leukemia (non-CML)/BCR-ABL-negative myeloproliferative neoplasms
(MPNs) include essential thrombocythemia (ET), polycythemia vera (PV), and primary myelofibrosis (PMF) (apart from chronic neutrophilic leukemia and chronic eosinophilic leukemia, which
are rare). They are uncommon clonal disorders of adults, with an incidence ranging
from 0.5 to 3/100,000 persons, BCR-ABL negative, and characterized by the activation
of Janus-associated kinase 2 (JAK2). Very few studies have been reported from India.
Aims and Objectives: The aims and objectives of this study were to analyze the clinicopathological spectrum
and to determine the frequency of JAK2 mutation in patients of non-CML/BCR-ABL negative
MPNs. Materials and Methods: Clinical and morphological features and frequency of JAK2 mutation in patients with
PV, ET, and PMF were studied at a tertiary care hospital. The material was retrieved
from the hematopathology records and reviewed. Results: JAK2V617F mutation was found in 10 of 14 cases (71%) of MPNs, 100% in PV, 50% in
ET, and 71% of idiopathic myelofibrosis. The presence of JAK2V617F mutation was associated
with a higher hemoglobin level (P < 0.05), a higher TLC (P < 0.05), and higher age (P < 0.05). Results showed that there are morphologic differences, and megakaryocytic
morphology represents a useful clue for the differential diagnosis of these three
BCR-ABL-negative MPN subtypes. Conclusion: The JAK2 V617F mutation was detected in 71% of patients with MPN disorders. Peripheral
blood mutation screening for JAK2 V617F should be incorporated into the initial evaluation
of patients suspected to have MPNs. Differences in megakaryocytic morphology provide
the histomorphological hallmark of BCR-ABL-negative MPN subtypes.
Keywords
Janus-associated kinase 2 mutation - marrow morphology - myeloproliferative neoplasm