Scientists in the Departments of Radiation Oncology and Medicine at the University of Washington (UW) and Fred Hutchinson Cancer Center (Fred Hutch) are directly targeting cancerous cells traveling through patients’ bloodstreams with diseases such as leukemia and lymphoma using an intravenous injection of the radioactive isotope astatine-211 (At-211). The work, its challenges, and its promise were described in a recent news release from the National Isotope Development Center (NIDC), which is managed by the Department of Energy’s Isotope Program.