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Which types of ionizing radiation are used in radiation therapy?

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linear accelerator; external beam radiation therapy — radiation therapy External beam radiation therapy (also known as external beam teletherapy, or long-distance therapy) being delivered using a machine known as a linear accelerator.

Radiation therapy utilizes various forms of ionizing radiation to damage the DNA of cancer cells, preventing their replication and causing them to die. These therapies are categorized into two primary groups: electromagnetic waves and particle radiation.12

Electromagnetic Radiation

X-rays: Commonly used in modern medicine, high-energy X-rays are directed at target tissues to treat malignant tumors.13
Gamma rays: Similar to X-rays, these high-energy waves are used to treat cancerous tumors and blood disorders.3

Particle Radiation

Particle beams involve the use of subatomic particles, which can be generated by linear accelerators or radioactive decay. These include:41
* Protons: Often used in particle beam therapy, protons are preferred for tumors near critical structures because they deposit energy at a specific depth (the Bragg peak) with minimal exit dose.51
* Electrons: Useful for treating certain skin cancers due to their lower penetration depth.2
* Heavy ions: Particles such as carbon ions are used for their physical advantages in treating specific slow-growing tumors.51
* Neutrons: Used in certain therapeutic applications to induce tissue damage.12