Figure 2.

Evidence of the portability of a biomarker’s ability to extend its discriminatory power to samples from independent and geographically distant clinical sites. (a) Plot of an unsupervised cluster analysis of samples from a prospective study at a single site. The plot shows the samples in the first two-dimensional principal component analysis (PCA) of data from seven ovarian cancer biomarkers (not including CA-125). (b) Using the same PCA projection coefficients from A, samples from five additional geographically distant clinical sites are plotted in the same two-dimensional PCA component space. The persistence of clustering patterns and separation between benign and malignant ovarian tumors from site to site is an important piece of evidence to support further IVDMIA development. Four of the seven biomarkers were late added to CA-125 to form the OVA1® (Vermillion, Inc., Austin, TX) biomarker panel.