Physics Colloquium

Proton therapy, an advanced cancer treatment technique that takes advantage of the unique properties of a beam of protons to sharply stop at a given depth in tissue, is well-established in radiation therapy. Compared with other types of radiation, proton therapy treatments offer improved dose conformality, delivering uniform doses to difficult-to-reach tumors while sparing nearby healthy tissue. In the past, the large scale and cost of a proton therapy system have limited access to the technology for many patients and raised questions about whether the clinical benefits warrant the additional cost. In recent years, the marketplace has seen the introduction of compact proton therapy systems: single-room systems with much smaller footprints and significantly reduced installation costs. Such compact systems are being adopted by hospitals with increasing frequency and have the potential to greatly expand patient access to this advanced treatment.

In this talk, we will briefly review the underlying physics and radiobiology behind proton therapy, as well as the computational techniques used to plan a radiation therapy treatment and beam shaping techniques used to deliver one. We will then discuss technological advances that have enabled the commercial introduction and success of compact proton therapy. New particle accelerator technology has produced accelerators of significantly reduced size and weight. Treatment facility architecture has taken advantage of these to reduce the overall system size while novel beam delivery technologies and techniques have maintained or improved the treatment performance even within the size constraints presented by a compact system. We'll conclude with a discussion of current challenges and potential future directions in proton therapy development.