“…Altogether persuasive evidence has been produced that even in prodromal stage PV histopathology plays a prominent role for establishing the diagnosis [58] in combination with JAK2V617F and related mutation studies [3,8,10,17,69,70,77,78], the determination of the Epo level [64,[79][80][81] and/or the laboratory intensive as well as timeconsuming cell culture studies [82,83] that are neither absolutely specific for PV [84][85][86] nor standardized for clinical use [87]. All patients developed overt polycythemic PV about 6 months to 2 years later, at the beginning 35 patients may be clinically mimic ET when applying the PVSG criteria [5,7,21].…”