Role of Proton Beam Therapy in Current Day Radiation Oncology Practice

Abstract

Proton beam therapy (PBT), because of its unique physics of no–exit dose deposition in the tissue, is an exciting prospect. The phenomenon of Bragg peak allows protons to deposit their almost entire energy towards the end of the path of the proton and stops any further dose delivery. Braggs peak equips PBT with superior dosimetric advantage over photons or electrons because PBT doesn’t traverse the target/body but is stopped sharply at an energy dependent depth in the target/body. It also has no exit dose. Because of no exit dose and normal tissue sparing, PBT is hailed for its potential to bring superior outcomes. Pediatric malignancies is the most common malignancy where PBT have found utmost application. Nowadays, PBT is also being used in the treatment of other malignancies such as carcinoma prostate, carcinoma breast, head and neck malignancies, and gastrointestinal (GI) malignancies. Despite advantages of PBT, there is not only a high cost of setting up of PBT centers but also a lack of definitive phase-III data. Therefore, we review the role of PBT in current day practice of oncology to bring out the nuances that must guide the practice to choose suitable patients for PBT.