Massachusetts General Hospital researchers have developed a microfluidics chip that effectively captures cancer cells, which make up just one in a billion cells in blood, in high enough numbers to analyze them for molecular markers.

Even before tumors metastasize, they shed a small number of cancer cells into the bloodstream. The ability to simply take a blood sample from a patient and then capture these cells and analyze them for specific molecular markers could provide ways for physicians to select the best drugs for patients, instead of the invasive surgeries they now perform to collect tumor tissue for molecular testing.a