A Comprehensive Evaluation of Circulating Tumor DNA and Circulating Tumor Cells as a Predictive Marker in Lung Cancer

A microsieve membrane filter device to effectively isolate circulating tumor cells from whole blood sample has been developed by the Institute of Bioengineering and Nanotechnology. The device exploits the size difference between cancer cells and blood cells to achieve the cancer cell capture on a microsieve filter with \> 85% recovery rate from 4.5-ml whole blood within 10 min, demonstrated with cancer cells spiked into whole blood samples. The device contains a densely packed pore array (\> 8000 pores/mm\^2) with an optimized pore diameter of 10 µm. Fluid regulation and cell counting are achieved by a simple vacuum pumping and laboratory fluorescence microscope. The captured cells are stained with anti-EpCAM-PE for CTCs, anti-CD45-FITC for white blood cells, and 4',6-diamidino-2-phenylindole (DAPI) for cell nuclei. The CTCs are identified with anti-EpCAM positive, anti-CD45 negative and DAPI positive, characterized using a fluorescence microscope.