Radioteraapiaga

Radioteraapiaga, commonly referred to as radiotherapy, is a medical treatment that uses ionizing radiation to damage the DNA of cancer cells, impairing their capacity to divide and grow. It can be used with curative intent, to shrink tumors and control disease, or palliatively to relieve symptoms. Radiotherapy may be applied as a standalone treatment or combined with surgery, chemotherapy, or immunotherapy.

Radiotherapy can be delivered externally (external beam radiotherapy, EBRT) or internally (brachytherapy). In EBRT, high-energy photons or particles are directed at the tumor from outside the body using linear accelerators, with treatment planned through imaging and computer-based dosimetry. Brachytherapy places radioactive sources close to or inside the tumor. A third approach, systemic radiotherapy, uses radiopharmaceuticals that travel through the bloodstream to target cancer cells.

Treatment planning relies on imaging (CT, MRI, PET) to define target volumes while sparing healthy tissue. Dosing is typically given in fractions over several days or weeks to optimize tumor control and minimize side effects.

Common side effects depend on the treated area and may include skin irritation, fatigue, and localized organ or tissue toxicity. Acute effects often resolve after treatment; late effects can emerge months to years later.

Advances in radiotherapy focus on precision and organ-sparing techniques, such as intensity-modulated radiotherapy (IMRT), image-guided radiotherapy (IGRT), and proton therapy, improving outcomes while reducing collateral damage.