Superconducting Cyclotrons for Hadron Radiotherapy

Superconducting magnets have been widely used in medical devices for several decades, primarily in thousands of MRI systems worldwide. More recently superconducting magnets have begun to have a small but growing impact on a newer field of medical devices, namely cyclotron accelerators for hadron therapy. This is a form of radiation treatment that uses ionized particle beams (instead of X-rays) to treat a wide variety of cancerous tumors, being particular effective for certain types of pediatric cancer. Although there is growing interest and demand in the medical community for hadron therapy systems, growth in this form of treatment system has been hampered by the very large infrastructure required by conventional accelerator and beam delivery systems, and their concomitant high capital costs. This issue is being addressed by the use of high field superconducting cyclotrons, which offer much more compact accelerators with reduced footprints, along with lower operating costs. In this paper, we describe the background and history of superconducting cyclotrons, and provide a survey of recent developments in this field of application. We also describe the design of a novel, ironless superconducting cyclotron being studied at the Massachusetts Institute of Technology (MIT), Cambridge, MA, USA, and how this technology could be a path towards significantly more widespread deployment of this form of cancer treatment.