This review examined PBT physical properties, treatment techniques including the recent advances in planning and delivery, and clinical outcomes for each of the major thoracic malignancies, including lung cancer, esophageal cancer, mesothelioma, thymic cancer, and primary mediastinal lymphoma.

The review pointed out that despite clear dosimetric benefit with PBT in thoracic radiotherapy, the improvement in clinical outcomes remains to be seen. Nevertheless, with the incorporation of newer techniques, PBT remains a promising modality and ongoing randomized studies will clarify its role to determine which patients with thoracic malignancies receive the most benefit. Re-irradiation, advanced disease requiring high cardio-pulmonary irradiation volume and younger patients will likely derive maximum benefit with modern PBT.