Molecular Classification of Myeloproliferative Disorders

Polycythemia vera, essential thrombocytosis, and primary myelofibrosis are myeloproliferative disorders (MPDs) with variable clinical presentations and outcomes. Currently, such MPDs are classified by cell counts, marrow morphology, and mutations in JAK2, CALR, or MPL.

Now, investigators have developed and validated a genomic classification model for MPDs using mutation analysis of 69 myeloid cancer–related genes from a retrospective cohort of 2035 MPD patients.

Of these patients, 45% had isolated mutations of JAK2, CALR, or MPL, and 33 genes were identified as driver mutations in five or more patients. Eight genomic MPD subgroups were established; patients with TP53 mutations had poor outcomes, and those with mutations in genes regulating ch…