Acute myeloid leukemia following a myeloproliferative neoplasm: clinical characteristics, genetic features and effects of therapy.

Acute myeloid leukemia (AML) is an uncommon, but often deadly complication of myeloproliferative neoplasms (MPN). Post-MPN AML usually occurs years after the initial MPN diagnosis with an average age of onset between 64 and 68 years. Chromosome abnormalities are common and many patients have cytogenetic changes that are associated with poor risk features. Post-MPN AML is characterized by acquired somatic gene mutations, but, interestingly, mutations thought to have an etiologic role in the MPN, such as JAK2V617F, are sometimes absent in the AML clone. Conventional AML-style treatment appears to have limited efficacy, although when coupled to allogeneic stem cell transplantation, some patients have long-term survival. Less-intensive therapies such as hypomethylating agents and the JAK inhibitor, ruxolitinib, may be effective in some patients. New treatments have prompted efforts to characterize therapeutic responses better.