Radyoterapi is a medical treatment that uses high doses of radiation to kill or damage cancer cells. It works by targeting specific areas of the body where tumors are located, helping to shrink them or prevent their growth. This therapy can be used alone or in combination with other treatments like cerrahi (surgery) and kemoterapi (chemotherapy). The procedure is typically painless and can be delivered externally through a machine or internally using radioactive materials. Patients may experience side effects, such as fatigue or skin irritation, but these often improve after treatment ends. Onkoloji specialists usually oversee the treatment process.