Monitoring Cancer

One way that cancer is thought to spread from its original site and metastasize elsewhere in the body is through cells that detach from the primary tumor and circulate in the bloodstream. Recent studies have shown that tracking blood levels of these circulating tumor cells could help monitor how well a cancer treatment is working. But because their concentration in the blood is so low, researchers have struggled to detect them with enough accuracy to be clinically relevant.

Three years ago, bioengineer Mehmet Toner and cancer biologist Daniel Haber of Harvard University reported making a microfluidic chip that captured these cells at a higher rate than other techniques. The chip had a good enough resolution for proof-of-principle studies, says Shannon Stott, a postdoc in Haber's lab, but analysis required an individual to scan thousands of images with a microscope--a process that takes about eight hours per sample and is therefore not amenable to diagnostic use in the clinic.

In the current work, a pilot study of prostate cancer patients led by Stott and Shyamala Maheswaran at the Mass General Hospital Cancer Center, and published in Science Translational Medicine, the researchers tested an automated imaging system. In addition to reducing analysis time by more than 75 percent, the scientists could use the imaging to analyze the cancer cells at different points--before and after tumor removal surgery and during hormone-based therapy.