CC BY-NC-ND 4.0 · Indian J Med Paediatr Oncol 2008; 29(04): 7-11
DOI: 10.4103/0971-5851.51398
Original Article

Polycythemia vera and essential thombocythemia - A single institution experience

Cecil Ross
Department of Medicine, St. John′s, Medical College Hospital Bangalore- 560034, India
Navya, Vanamala,
Karuna Rameshkumar
Department of Clinical Pathology, St. John′s, Medical College Hospital Bangalore- 560034, India
› Author Affiliations


Background: In myeloproliferative disorders, occurrence of Janus kinase 2 [JAK2] mutation is a significant factor in pathogenesis in polycythemia rubra vera (PRV) and Essential thrombocythemia (ET). We studied the frequency of JAK2 mutation in patients with PRV and ET and to compare clinical and laboratory features of patients positive and negative for mutation. Patients and Methods: Clinical and laboratory features of PRV and ET patients (WHO criteria) from 1997 to 2004 were included. After morphological diagnosis, presence or absence of JAK 2 mutation was done during follow up and follow up details were recorded. Results: A cohort of 39 patients (ET-17, PRV -14, ET- PRV-8) were identified .The mean age of entire cohort was 55.5+14.5 years. Comparison of clinical and laboratory features showed JAK2 positive patients were older by a decade, had higher frequency of splenomegaly and higher values for hemoglobin (16.5+2.6 gm/dl) and neutrophil counts (14.5+4.8 thousand/μl).During the course of follow up (6 to 106 months; mean 25.5+28.6 months) frequency of thrombotic events in both groups (p value >0.05) was same, though time for occurrence for thrombotic event was shorter in JAK 2 positive patients, which is noteworthy. Conclusions: The identification of JAK 2 mutation probably defines a sub entity in ET with aggressive behavior as evidenced by splenomegaly, higher total counts and transformation to PRV (n=6/8). The onset of JAK2 V617F mutation probably heralds progression to PRV.

Publication History

Article published online:
19 November 2021

© 2008. Indian Society of Medical and Paediatric Oncology. This is an open access article published by Thieme under the terms of the Creative Commons Attribution-NonDerivative-NonCommercial-License, permitting copying and reproduction so long as the original work is given appropriate credit. Contents may not be used for commercial purposes, or adapted, remixed, transformed or built upon. (

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