Overview
Radiation therapy uses high-energy radiation, such as X-rays, to damage cancer cells so they can no longer grow or divide. It may be used to try to cure cancer, shrink a tumor before surgery, lower the chance of cancer returning, or help relieve symptoms. Treatment is usually planned by a radiation oncology team using imaging and detailed measurements.
Who Is Affected
People with many different cancers may be offered radiation therapy, including cancers of the breast, prostate, head and neck, lung, brain, cervix, skin, and others. Children and adults can both receive it, but treatment plans are tailored to age, cancer type, stage, and overall health. Not everyone with cancer needs radiation therapy.
Diagnosis and Tests
Before treatment starts, the care team confirms the cancer diagnosis and stage using tests such as imaging scans, biopsies, and blood tests. A planning visit, often called simulation, helps map the exact treatment area. Special scans and body positioning tools may be used so the radiation is delivered as accurately as possible.
Treatment Categories
External beam radiation therapy delivers radiation from a machine outside the body. Internal radiation therapy places a radiation source inside the body, either near or inside the tumor; this is often called brachytherapy. Some people may also receive systemic radiation, in which a radioactive medicine travels through the body. Radiation therapy may be combined with surgery, chemotherapy, immunotherapy, or hormone therapy depending on the treatment plan.
Living With It
Many people continue some usual activities during radiation therapy, but tiredness is common and may build up over time. Side effects vary by treatment area and can include skin changes, soreness, hair loss in the treated area, trouble swallowing, bowel or bladder changes, or other local symptoms. Ask the treatment team which side effects to watch for and how to report them early.
Diet and Lifestyle
Eating enough food and drinking enough fluids can be important during treatment, especially if side effects affect appetite, swallowing, or digestion. Gentle activity may help some people manage fatigue, but rest is also important. Skin in the treated area may need special care, so follow the radiation team's instructions about washing, sun exposure, and products to avoid.
When to Seek Medical Care
Contact your treatment team if side effects are getting worse, if you cannot eat or drink enough, or if pain, skin breakdown, fever, vomiting, diarrhea, breathing symptoms, or urinary problems develop. Also seek medical advice if you feel unusually weak, dizzy, confused, or unable to manage daily activities. Prompt communication can help the team adjust support and check for complications.
When It May Be an Emergency
Get urgent medical help right away for severe shortness of breath, chest pain, heavy bleeding, seizures, sudden confusion, fainting, severe dehydration, or signs of a serious allergic reaction. People receiving cancer treatment may also need urgent evaluation for high fever or possible infection. Follow local emergency guidance and your cancer team's instructions.
Questions to Ask a Healthcare Professional
You may want to ask why radiation therapy is being recommended, what type will be used, how long treatment will last, and what side effects are most likely for your situation. It can also help to ask how treatment may affect work, school, fertility, sexual health, and daily routines. Ask whom to contact after hours if problems happen between appointments.