About Radiation Therapy

What is radiation therapy?

Radiation therapy is a localized and selective cancer treatment. In 70% of cases its objective is to cure the cancer by using an adequate dose of radiation, therefore destroying the cancer cells and in the meantime preserving as much surrounding healthy tissue as possible. To do so, high-energy radiations are used to shrink tumors by blocking the multiplication cycle and to kill the cancer cells. X-rays, gamma rays, and charged particles are types of radiation used for cancer treatment.1

For 50% to 60% of patients with cancer, radiotherapy is part of their regular cancer treatment. This therapy can be used in combination with surgery and/or chemotherapy.2-4

A number of factors will be taken into consideration to make sure each patient has the right individualized specific treatment, such as the type of tumor, localization, radiation time, etc.

Radiation therapy can be distinguished in external and internal radiotherapy. When radiations are delivered by a machine outside the body it is called external radiotherapy. The beams will go through the skin before reaching the tumor.

There is another type of radiation therapy called metabolic radiotherapy. The radioactive device is given orally (through drink or capsule) or by intravenous injection. Once swallowed or injected the devise fixes itself upon the cancer cells to destroy them.

In 30% of cases, radiotherapy is used as a palliative to:

  • Reduce the size of tumors before undergoing a surgical procedure
  • Reduce the risk of relapse after tumor removal surgery
  • Reduce the risk of tumor metastasis
  • Relieve the patient


1. Lawrence TS, Ten Haken RK, Giaccia A. Principles of Radiation Oncology. In: DeVita VT Jr., Lawrence TS, Rosenberg SA, editors. Cancer: Principles and Practice of Oncology. 8th ed. Philadelphia: Lippincott Williams and Wilkins, 2008.
2. Naylor W, Mallett J. Management of acute radiotherapy induced skin reactions: a literature review. Eur J Oncol Nurs. 2001 Dec;5(4):221-33.
3. Porock D, Kristjanson L. Skin reactions during radiotherapy for breast cancer: the use and impact of topical agents and dressings. Eur J Cancer Care. 1999 Sep;8(3):143-53.
4. Lopez E, Nunez MI, Guerrero MR, del Moral R, de Dios Luna J, del Mar Rodriguez M, et al. Breast cancer acute radiotherapy morbidity evaluated by different scoring systems. Breast Cancer Res Treat.2002 May;73(2):127-34.

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