How does radiation therapy treat malignant tumors?

1 Answer
May 29, 2017

Radiation therapy uses ionising radiation as part of cancer treatment to control or kill malignant cells.


Radiation therapy is commonly applied to the cancerous tumor because of its ability to control cell growth. It works by damaging the DNA of cancerous tissues leading to cellular death. It can either damage DNA directly or create charged particles within the cells that can in turn damage the DNA. Different cancers respond to radiation therapy in different ways.

The DNA damage is caused by Photon therapy or Charged particles.

Photon Therapy
Most of the radiation effect is by free radicals. Cancer cells are generally less differentiated and more like stem cells. They reproduce more than most healthy differentiated cells and have a diminished ability to repair sub lethal damage. Damage to the cancer cell DNA accumulates, causing them to die or reproduce more slowly.

Charged Particle Therapy
Charged particles (protons and boron, carbon and neon particles) can cause direct damage to cancer cell DNA through light energy transfer. These have an anti tumor effect causing double stranded DNA breaks.