Radiotherapy is a form of medical therapy which involves the use of ionizing radiation. It is most typically used to treat cancers and tumors, and also to prepare the body for bone marrow transplants, in which case the entire body is irradiated. There are a number of different types of radiotherapy, and doctors usually decide on the best choice after consulting with the patient and with other medical professionals who have experience in oncology and radiation therapy.
Ionizing radiation has been used as a medical treatment since 1899, when it was used to treat breast cancer. However, until the 1930s, doctors did not realize the full extent of the possible side effects of radiotherapy. They often delivered doses which were too high, and they failed to protect themselves and their support staffs from harmful radiation. As research on radioactive isotopes and ionizing radiation continued, radiotherapy changed dramatically, and the modern version of this medical treatment is much safer.
In external radiotherapy, ionizing radiation is aimed at the patient from outside the body, typically with the use of a beam which directs the radiation. Some patients are tattooed, to create a focus for the beam to target on. X-rays, gamma rays, and particle beams are all used in external radiotherapy. In internal radiotherapy, the radiation is actually inside the body, either in the form of implants which are later removed, or in ingestable or injected form.
One commonly voiced concern about radiotherapy is the idea that it will make the patient radioactive. This is not the case with external radiotherapy, but internal radiotherapy can in fact cause a patient to be mildly radioactive. In the case of patients who ingest radioactive isotopes, their body wastes will be radioactive for a brief period, necessitating careful handling.
The goal of radiotherapy is to damage the cells of a cancer or tumor to prevent reproduction. This treatment is usually used in conjunction with other forms of medical treatment which are designed to make the patient more comfortable while also hopefully eliminating the cancer or tumor. In some cases, radiotherapy is used in palliative care, when it becomes evident that a patient is likely to die, but he or she is still experiencing pain from tumors or cancerous growths. In these instances, medical personnel are aware that the radiation will not cure the patient, but it could reduce pain.
When radiotherapy is recommended for a patient, an oncologist will go over the risks and benefits carefully, allowing the patient to make an informed choice. Depending on the type of radiotherapy being prescribed, the radiotherapy may be an outpatient procedure, or the patient may need to be hospitalized.