TF and essential thrombocythemia: In that concerning the expression of the CD142 procoagulant marker (TF), we found that only VTE patients had significantly higher numbers of CD142+ CEC (median: 309 cells/ml; range 93–2532) than healthy control (median: 77 cells/ml; range: 0–366) (p<0.001), no differences being observed between the CD142+ CEC counts from patients with MPN (ET or PV) and controls.