Plasma microparticles are not elevated in fresh plasma from patients with gynaecological malignancy — An observational study

ObjectivesGynaecological cancer is common. It is highly amenable to effective treatment, but thrombosis remains a common complication. There is controversy about whether microparticles (MPs), particularly tissue factor (TF) positive MPs, are increased in patients with malignancy and/or thrombosis. We therefore set out to investigate the relationship between MPs of different cellular origins, in patients with gynaecological malignancy. We hypothesised that patients with gynaecological malignancy have increased numbers of MPs. We measured MPs released by different cell types in these patients, and correlated the results with measures of haemostatic activation.MethodsWe measured the number of platelet-derived MPs (PMPs), endothelial cell-derived MPs (EMPs), leucocyte-derived MPs (LMPs), TF+ve MPs and annexin V (AV) binding MPs in fresh plasma by flow cytometry in patients with gynaecological malignancy and a control group. We also measured D-dimers, prothrombin fragments 1 and 2 (PF1&2) and thrombin–antithrombin (TAT) complexes as indirect markers of haemostatic activation.ResultsThe number of MPs (from all cell types) was similar in the two patient groups, with no significant differences. The number of circulating TF+ve MPs was also similar between the two groups. D-dimers (p < 0.001) and PF1&2 (p = 0.009) were significantly higher in the malignant group reflecting haemostatic activation, but there was no correlation between the level of D-dimers, PF1&2 and TAT and MP numbers.ConclusionUsing fresh samples, MPs were not significantly increased in patients with gynaecological malignancy. There was, however, evidence of haemostatic activation in the patients with malignancy, but no correlation between the number of MPs and haemostatic activation.

► Number of microparticles in patients with gynaecological malignancy and a control group with no malignancy.
► There was no difference in the number of circulating microparticles between the two patient groups.
► There was no correlation between the number of circulating microparticles and indirect markers of haemostatic activation.