Proton therapy: a perfect slice of physics, mathematics, and biology


Ke Sheng, Ph.D.,

FAAPM, Professor and Vice Chair of Medical Physics

Department of Radiation Oncology, University of California, San Francisco

FRI, 03/124/2023 - 3:00PM TO 4:00PM

Radiotherapy delivers an ionizing cytotoxic dose to both tumors and normal tissues. Research in the past decades has focused on reducing normal tissue dose. Protons emerged as an appealing modality for radiotherapy due to their superior physical properties. Compared with X-rays, protons release most of their energy at the Bragg peaks and leave no exit doses. The superior physical dose distribution also comes with a cost of range uncertainties. Besides the physical properties, protons also show intriguing radiobiological properties related to their variable energy transfer rates. These physical and biological properties create a mathematical optimization problem that is exciting and challenging. The talk will briefly describe the evolution of radiotherapy technology leading to modern proton therapy and then provide a deep dive into the proton planning problems.

Dr. Ke Sheng graduated from the University of Science and Technology of China with B.S. and M.S. before obtaining his Ph.D. in Medical Physics from the University of Wisconsin, Madison, in 2004. He was then an Assistant and Associate Professor at the University of Virginia. In 2011, Dr. Sheng moved to the University of California, Los Angeles, where he was promoted to Full Professor with Tenure and Director of Physics Research. In 2022, he joined UCSF Radiation Oncology as the Vice Chair of Medical Physics. He has broad research interests related radiotherapy and medical imaging, including treatment planning, optimization, image reconstruction, processing, machine learning, robotics and radiobiology. He was elected Fellow of AAPM in 2016. His research has been supported by NIH, DOE, and industrial partners.