Dr. Philip Thorpe and Ralph Mason (IMAGE) UT Southwestern Medical Center Caption Drs. Philip Thorpe (left), professor of pharmacology, and Ralph Mason, professor of radiology, have shown in animals that arsenic linked to a drug that binds to the blood vessels of cancerous tumors provides a powerful imaging agent. Credit UT Southwestern Medical Center Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.