Proton beam therapy for the treatment of esophageal cancer.

Radiation therapy (RT) has become an important component in the curative management of esophageal cancer (EC) worldwide. Since most of the ECs seen in the Western hemisphere (i.e., Europe and the United States) are located in the mid- to distal-esophageal locations, heart and lungs invariably receive significant radiation doses. Much of the normal tissue exposure could be reduced with the utilization of advanced radiation technologies, notably intensity modulated radiation therapy (IMRT). Proton beam therapy (PBT) provides the ability to even further reduce normal tissue exposure because of its lack of exit dose, which is expected to provide clinically meaningful benefit for at least some EC patients. Herein, we provide an overview of the comparative effectiveness of proton versus photon therapy, summarize the published clinical experience, and describe the future outlook of PBT development in EC.