Jamile M. Shammo, MD, provides insight on the effect of risk factors on prognosis and mortality in patients with polycythemia vera, including the risk for transformation to myelofibrosis and acute myeloid leukemia.
Jamile M. Shammo, MD: Risk stratification employed a variety of points or patient characteristics, including age, white blood cell count, presence of peripheral blast, and anemia. And for each risk stratification schema that was developed initially with the allele score, then the IPSS, and then the dynamic IPSS—including whether there would be thrombocytopenias, abnormal cytogenetics and transfusion need—you basically create certain categories that have been associated with the survivals and outcomes. And, again, all those risk stratification schemas have been modified to include some of the newer information regarding molecular risk stratification, etc. And so, I think it does evolve in time to make it a little bit more personalized, if you will. But generally speaking, you have perhaps several broad categories that give you an idea about survival, and they may be helpful in risk stratification in PV—I think more so in the myelofibrosis than PV because of the consideration for transplantation in that area.
The risk of transformation to myelofibrosis has been quantitated and it’s like 8% to 9% at 10 years. And then, after that, it’s perhaps 7% to 8% at 20 years for acute leukemia.
There’s some suggestion that patients who have more fibrosis at the time of diagnosis perhaps have a higher chance of progression to a myelofibrosis, and, hence, acute leukemia. But again, I think that has to do with how long a patient has been living with the disease before a bone marrow has been done. And then, I think there’s also another element we haven’t even talked about, which is the presence of other mutations together with JAK2. I think we’re understanding a lot more about what the influence of additional mutations could be on the prognosis of patients who have PV relative to both—myelofibrotic transformation and leukemia transformation.
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