Abstract Proton is formed after hydrogen atom loses an electron with a positive charge of particle (H+).After the proton is accelerated,it possesses significant advantages in terms of the distribution of physical dose compared with the photon. Currently,proton radiation has captivated extensive attention and has been actively applied in clinical practice. Nevertheless,due to the small amount of proton facilities and lack of clinical trials,the proton therapy,especially the radiobiological characteristics and biological effect of photon radiotherapy has been poorly understood. In this article,these issues were summarized as below.
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