US scientists have developed a method to pluck circulating cancer cells from the bloodstream so that they can be analysed to monitor a patient's response to treatment. The device, which has been Massachusetts General Hospital researcher Daniel Haber and his team and is presented in the New England Journal of Medicine, is a microfluidic device called a CTC-chip, short for circulating tumour cell chip. It contains 78,000 'microposts' coated in an antibody that locks onto cells bearing a lung cell marker called EpCAM - epithelial cell adhesion molecule.
"If tumour genotypes don't remain static during therapy, it's essential to know what you are treating at the time you are treating it," says Haber. "Biopsy samples taken at the time of diagnosis can never tell us about changes emerging during therapy or genotypic differences that may occur in different sites of the original tumour, but the CTC-chip offers the promise of non-invasive cancer monitoring."