Current status and prospect of particle therapy for esophageal cancer.

Esophageal cancer is among the top causes of cancer-related mortality worldwide, and the main treatment modality for locally advanced esophageal cancer is concurrent chemoradiotherapy. The current photon-based radiotherapy modalities and procedures have increased the incidence of treatment-related cardiac and pulmonary complications. Additionally, anatomical changes in the esophagus resulting from diaphragmatic movement, weight loss, and tumor progression present challenges for radiotherapy. These challenges have spurred interest in particle therapies, such as proton beam therapy (PBT) and heavy-ion therapy, for esophageal cancer. This paper comprehensively reviews the dosimetric advantages, clinical efficacy, and limitations of PBT and heavy-ion therapy for esophageal cancer and discusses their prospects. This highlights the unique dosimetric benefits of these therapies, particularly their ability to deliver high-dose radiation precisely to the tumor while sparing the surrounding normal organs and tissues. Although PBT and heavy-ion therapy demonstrate superior clinical efficacy compared to photon therapy, they are not without limitations. Multiple studies are needed to further validate and supplement the existing clinical and preclinical data to better exploit the benefits of PBT and thereby provide improved survival advantages to these patients.