What are the different types of radiotherapy?

SHORT VERSION

There are two main types of radiation therapy:

  • – external radiation therapy
  • – internal radiation therapy (brachytherapy)

External radiation therapy uses a linear particle accelerator to create a beam of radiation that passes through the skin and tissues to reach the area to be treated.

In brachytherapy, the radioactive source is directly implanted in contact with the area to be treated.

There are two main types of radiotherapy: external radiotherapy and brachytherapy.

In external radiation therapy, the radiation is emitted from a device called a linear particle accelerator (or Linac). The radiation beam is directed to the tumor to be treated. The radiation will pass through the skin and healthy tissue, painlessly, to reach the area (volume) to be irradiated. The two most commonly used radiation types are X-rays(also called photons, the most frequently used) and electrons (for superficial tumors). There are different external radiation therapy methods, for instance three-dimensional (3D) conformal, intensity-modulated,and stereotactic radiation therapy.. The treatment plan and its main parameters (i.e. irradiation technique, volume to be irradiated, total dose, dose per session, and total number of sessions) will be determined by a medical specialist called a radiation oncologist.

In brachytherapy, radioactive sources are implanted inside the body, close to the area to be treated,. during a specific surgical procedure that may require general or loco-regional anesthesia.. As these radioactive sources emit ionizing radiation directly in contact with the tumor, the doses received by the healthy tissues are very limited. X-rays are not used for brachytherapy, but other types of radiation with equivalent capacity to destroy tumor cells.

The choice between brachytherapy and external radiation therapy depends on the tumor nature and location.