Thanks for your help with this week’s case!
We discussed a 55 year old man who presented with persistent erythrocytosis, thrombocytosis, and leukocytosis. This was associated with a thrombotic event (myocardial infarction).
Further investigations revealed JAK2 V617 positivity and a bone marrow showing hypercellularity, left shifted granulopoiesis, megakaryocyte clustering. Reticulin was not increased.
He was diagnosed with polycythaemia vera (myeloproliferative neoplasm) and commenced urgent venesection to reduce his thrombotic risk. This resulted in symptomatic iron deficiency and he was commenced on cytoreductive treatment with hydroxycarbamide.
He required high doses of hydroxycarbamide to achieve disease control and this was accompanied by significant side effects. He was switched to ruxolitinib therapy with good effect.
However, after a year he became pancytopenic and further bone marrow assessment showed his condition had progressed to myelofibrosis. Due to his age and performance status, he was referred for an allogeneic stem cell transplant.
Myeloproliferative neoplasm is a term used to describe a heterogeneous group of bone marrow disorders. Polycythaemia vera is an example of this and its morbidity and mortality are mainly associated with its increased risk of thrombosis and progression to myelofibrosis and acute myeloid leukaemia.
The British Society of Haematology have recently published helpful guidance on how to diagnose and manage this condition: https://onlinelibrary.wiley.com/doi/full/10.1111/bjh.15647