Treatment for more advanced and difficult-to-treat head and neck cancers can be improved with the addition of polyvinyl alcohol (PVA), the same ingredient used in children's glue. Researchers found that combining PVA with a boron-containing compound, D-BPA, improved the effects of a type of radiation therapy for cancer, compared to currently clinically used drugs. The PVA made the drug more selective of tumor cells and prolonged drug retention, helping to spare healthy cells from unnecessary radiation damage.