Background: In breast cancer therapy predictive and prognostic markers are derived from the primary tumor but systemic therapy aims at eliminating the remnant tumor cells left in the body after surgery which the cells circulating in peripheral blood are part of. For individualized therapy, therefore, it would be advantageous to better characterize this remnant disease for more targeted therapeutic approaches. Materials and Methods: 10 to 20 single live epithelial antigen positive cells were isolated from peripheral blood of 50 newly diagnosed breast cancer patients using the automated capillary cell isolation system of the MMI CellEctor and individually deposited under visual control onto Ampli Grid slides (Advalytics). The mRNA was the reverse transcribed and amplified using primers for 6 different tumor associated targets among them EpCAM and Her2/neu.

Results: Expression profiling could be successfully performed from more than 80% of all individually deposited isolated cells demonstrating the epithelial nature of these cells but also heterogeneity among the cells of in individual patients with respect to other genes. Thus we show that circulating epithelial cells from breast cancer patients can be individually deposited and these single celsl can subsequently be subject to expression profiling.

Discussion: Further analysis by high through-put profiling of the remnant tumor burden in breast cancer patients after surgery comprising the cells circulating in peripheral blood may contribute to better characterize the targets of systemic therapy in order to individualize cancer therapy.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P3-10-37.