answered on 7 Jun 2019:
last edited 7 Jun 2019 8:12 am
Radiation therapy seeks to eliminate cancer cells by irradiation-induced DNA damage. Paradoxically, recent research findings have implicated X-day radiotherapy(photons in tumour recurrence, metastasis and radio-resistance. This has been linked in part, to an X-irradiation-induced up-regulationof the Hedgehog(Hh) signalling pathway.
X-rays and gamma rays are both types of high energy (high frequency) electromagnetic radiation. They are packets of energy that have no charge or mass (weight). These packets of energy are known as photons.
Both x-rays and gamma rays are forms of high-frequency ionizing radiation, which means they have enough energy to remove an electron from (ionize) an atom or molecule. Ionized molecules are unstable and quickly undergo chemical changes. Beams of x-rays and gamma rays can be used in a guided fashion using measured doses to destroy cancer cells. They achieve this through ionising DNA in cancer cells, forcing the cancer cells to undergo programmed cell death, and hence the tumour shrinks. A bystander effect/damage of healthy cells surrounding the tumour cannot be avoided using Gamma rays, but this can be achieved using a sharp beam of deeply penetrating heavy ions such as carbon ions and protons, as applied in hadron therapy.
Refer to my MSc thesis here for further information on radiotherapy using x-rays (equivalent to gamma) rays compared to hadron therapy.