Prof. Zelig A. Tochner, MD is Emeritus Professor of Radiation Oncology at the University of Pennsylvania and former Vice Chair and Clinical Director of the Roberts Proton Therapy Project, where he helped establish one of the world's leading proton therapy centers. A graduate of the Hebrew University–Hadassah Medical School, he previously served as Head of Oncology at Hadassah University Hospital and as a physician-scientist in the Radiation Oncology Branch of the U.S. National Cancer Institute (NIH). He is internationally recognized for pioneering advances in proton therapy, pediatric and neuro-oncology, and precision radiation treatment.