Circulating microparticles in breast cancer patients: a comparative analysis with established biomarkers.

BACKGROUND The aim of the present prospective case-control study was to evaluate the putative relevance of circulating microparticles (MP) as a biomarker in breast cancer patients. MATERIALS AND METHODS Endothelial cell-(EMP) and leukocyte-derived MP (LMP) were determined by flow cytometry in breast cancer patients (n = 41) and healthy controls (n = 25) and compared to carcinoembryonic antigen (CEA), cancer antigen (CA)15-3 and von Willebrand factor antigen (vWF) levels by specificity-sensitivity profiles. RESULTS LMP, CEA and CA15-3 levels differed significantly between breast cancer patients and controls, whereas EMP and vWF did not. The specificity-sensitivity profiles of LMP and CA15-3 were similar. CONCLUSION Increasing levels of circulating LMP (CD45+), CEA and CA15-3 correlated with increasing tumor size, thus reflecting disease stage. LMP showed an equal specificity-sensitivity profile to the established marker CA15-3 and therefore might have the potential to become a new biomarker in breast cancer patients.