How do you differentiate between JAK2 positive ET and PV when peripheral blood shows erythrocytosis and thrombocytosis?  

The answer to this question is very simple. Before the discovery of erythropoietin and accurate assays for it, and before the discovery of JAK2 driver mutations, the diagnosis of polycythemia vera was clinically-based. The Polycythemia Vera Study Group (PVSG) did an extensive epidemiologic study and...

I imagine a pathologist would have a more precise answer here, however, when I see both thrombocytosis and erythrocytosis (especially with leukocytosis), I think the patient likely has PV as this disease is characterized by panmyelosis. The bone marrow morphology can further clarify the diagnosis- E...