What type of particles are used in proton therapy to deliver radiation?

Proton therapy specifically utilizes positively charged protons to deliver radiation to cancerous tissues. Protons are heavy particles compared to other forms of radiation like electrons and photons (which comprise X-rays), allowing for a targeted approach to treatment. One of the key advantages of protons is their ability to deposit the majority of their energy directly at a specific depth (the Bragg peak), which minimizes damage to surrounding healthy tissues while effectively treating tumors. This precision is particularly beneficial in complex cases, such as tumors located near critical structures or in pediatric oncology, where reducing radiation exposure is crucial. The effectiveness and safety of proton therapy stem from this unique property of protons being able to focus their energy more accurately than other types of particles used in radiation therapy.