Scientists have developed a noninvasive device that may not only detect melanoma cells traveling through the bloodstream, but also kill them. The device, which the investigators call Cytophone, accurately detected cancer cells in 27 out of 28 people with melanoma. It also reduced the amount of cancer cells in participants’ blood, suggesting that it may kill the cells. The device uses laser beams and sound waves to scan circulating blood for melanoma cells. It does not require any needles or blood draws and can scan a person’s entire volume of blood—about 5 liters—in a matter of hours. The NCI-funded study demonstrated the feasibility of using the device to detect cancer cells in the blood of people with melanoma, said the study’s senior investigator, Vladimir Zharov, Ph.D., D.Sc., director of the Arkansas Nanomedicine Center at the University of Arkansas for Medical Sciences. “One problem with detecting circulating tumor cells is that they are found in very small amounts in blood,” said Miguel Ossandon, Ph.D., of NCI’s Division of Cancer Treatment and Diagnosis, who oversaw the study’s funding. According to the findings, published June 12 in Science Translational Medicine, the Cytophone device was able to detect a single cancer cell in a liter of blood, making it about a thousand times more sensitive than existing technologies that are used to search out circulating cancer cells. Dr. Zharov and his team hope to build more devices so that they can conduct a larger study of more patients with melanoma. And although this approach can only detect cells that have pigment, with some modifications it is also applicable to cancers other than melanoma, noted lead author Ekaterina Galanzha, M.D., Ph.D., of the University of Arkansas for Medical Sciences. For example, by using nontoxic gold nanoparticles, the team used a similar approach to detect circulating breast cancer cells in mice and in blood samples from patients with breast cancer, she explained.