Radiaatiota

Radiaatiota is a medical treatment that uses ionizing radiation to damage the DNA of cells, primarily to control or kill cancer cells. It can be used with curative, palliative, or preventive aims and is commonly part of multimodal cancer care alongside surgery and chemotherapy. The term encompasses several delivery methods, including external beam radiotherapy, brachytherapy, and systemic radiopharmaceuticals.

External beam radiotherapy delivers high-energy photons or particles from outside the body, typically via a linear accelerator, and targets the tumor with carefully shaped beams while sparing normal tissue as much as possible.

Brachytherapy places radioactive sources inside or next to the tumor, delivering high doses over a short distance, while systemic radiopharmaceuticals circulate in the bloodstream to accumulate in certain tissues.

Treatment planning uses imaging and computer dosimetry to define the target volume and organs at risk. Doses are delivered in fractions, often daily over several weeks; total doses commonly range from about 20 to 70 Gy, depending on cancer type.

Common indications include cancers of the breast, prostate, lung, and head and neck, as well as palliative relief for advanced disease. Noncancerous conditions may also be treated in some cases.

Safety measures include shielding, immobilization, image guidance, and regular quality assurance of equipment. Acute side effects relate to the treated area and may include skin irritation and fatigue; late effects can include fibrosis or secondary cancers.

Advances such as intensity-modulated radiotherapy (IMRT), image-guided radiotherapy (IGRT), stereotactic body radiotherapy (SBRT), and particle therapy (protons or heavier ions) have improved targeting and reduced side effects.