GDF15 and acquired polycythemia vera: The median serum GDF15 levels in all these disease categories were significantly elevated relative to the levels in healthy controls: AML, 4078 pg/mL; MDS, 3249 pg/mL; CML, 1393 pg/mL; PMF, 5425 pg/mL; PV, 2458 pg/mL; ET, 2732 pg/mL; MM, 2074 pg/mL; ML, 2197 pg/mL; ALL, 1780 pg/mL; ATL, 2213 pg/mL; and healthy controls, 505 pg/mL (Fig.1).