La radiotherapy consists of sending radiations (also called rays or radiation) to destroy cancer cells by blocking their ability to multiply, while maintaining, as much as possible, healthy tissue and organs close to the tumor. We are then talking about a locoregional cancer treatment, that is to say, relating to a region of the body. Some adverse effects may appear such as an inflammatory reaction to irradiation, severe fatigue or even, especially for the treatment of certain gynecological or prostate cancers, fertility problems.

What are the types of radiation therapy?

Depending on the stage of the cancer and the organ affected, the shape and intensity of the rays vary. There are three main types of radiation therapy, which are external radiation therapy, brachytherapy, and metabolic radiation therapy.

La external radiation therapy is the most common type of radiation therapy used to treat cancer. The patient is subjected to X-rays, often emitted by a machine called a linear particle accelerator (LINAC). These rays will pass through the skin to reach the tumor area.

During a Brachytherapy, the radioactive elements (most often iridium or iodine-125) will be placed inside the body, in direct contact with the tumor (plesiocuritherapy) or inside the tumor (interstitial brachytherapy).

Finally, the metabolic radiation therapy (also called vectorized internal radiation therapy) consists in administering the radioactive source orally (drink or capsule) or intravenously. During this treatment, elements (such as radium or lutetium) will be made unstable, i.e. radioactive. These radioactive elements are called radionuclides. They will then be linked to molecules capable of targeting organs affected by cancer. Guided by the molecule in this way, the radionuclide will more easily penetrate the tumor cells of the organ concerned.

‍

What is a Gy?

One Gray (Gy) is the unit of measurement for measuring the dose of radiation absorbed by the patient, that is to say the Quantity of energy sent. One Gy corresponds to the energy of one joule (J) absorbed in 1 kg (kilogram) of matter. This unit is important in order to prescribe the most appropriate treatment to the patient.

‍

New radiotherapy treatments, sometimes in combination with other treatments, are regularly developed and must, before being used in clinical routine for patients, go through phases ofclinical trials. You can find out about these radiotherapy trials by connecting to the Klineo platform.

‍

‍

Sources: National Cancer Institute, Hospices Civils de Lyon, Hospices Civils de Lyon, Gustave Roussy Institute, Arcagy gyneco, Canadian Cancer Society