Radiotherapy: a guide to radiation treatment

Radiotherapy uses carefully planned radiation to damage cancer cells while limiting exposure to nearby healthy tissue.

It may be given from a machine outside the body, or delivered close to a tumour with an internal source. The aim can be to treat a cancer, lower the chance of cancer returning in an area, or ease symptoms caused by a tumour.

Before treatment, the team maps the target area with scans and makes a plan that shapes the radiation beams. You may have small skin marks or a fitted support to help you lie in the same position each visit.

During an external treatment session, you lie still while the machine moves around you. Staff watch and speak with you from outside the room. Radiation is not felt as it is delivered, and you do not become radioactive after external radiotherapy.

Effects depend on the body area receiving radiation. Tiredness, skin soreness, irritation of nearby organs, and temporary changes to appetite or bowel and bladder habits can occur. Some effects begin during treatment, while others emerge later.

Contact your treatment team promptly for fever, rapidly worsening pain, heavy bleeding, new shortness of breath, inability to pass urine, severe diarrhoea, or skin that is blistering or weeping. The team can assess whether symptoms need urgent treatment or a change in supportive care.

The expected benefit is individual: it depends on the cancer type, its location, whether cancer has spread, and the purpose of treatment. Radiotherapy may be used alone or combined with surgery, medicines, or both.

Your oncology team uses imaging, pathology results, previous treatment and your general health to discuss what treatment is intended to achieve. Follow-up looks for response, manages lasting effects and considers any next treatment that may be appropriate.

Planning is as important as delivery because it defines the treatment area and protects nearby structures. Appointments are usually outpatient visits, although some internal techniques require a procedure or a short hospital stay.

Radiotherapy is considered for many cancers, including Breast Cancer, Bowel Cancer and Brain Tumour, as well as for certain skin cancers and cancers affecting bone. It can also be considered when a tumour is causing pain, pressure or bleeding.

A radiation oncologist weighs the target area against nearby organs, previous radiation to that area, other planned treatments, pregnancy status where relevant, and your ability to attend appointments.

The process starts with a consultation and planning scan. The team then creates and checks a personalised plan before treatment begins. At each visit, positioning checks help match your planned position, followed by delivery of the radiation.

A review during treatment gives you a chance to discuss symptoms, medicines and practical problems such as eating, sleep or travel. Keep any support devices and appointment instructions unless the team advises otherwise.

Many people continue normal activities with adjustments for fatigue. Acute reactions can continue for a time after the final session before settling. The team will explain which changes are expected for your treatment area and when follow-up will occur.

Radiation can affect healthy tissue in the treatment field. Depending on the area treated, later effects may include firmness of tissue, swelling, changes in bowel, bladder, sexual or hormonal function, or damage to a nearby organ. Ask which specific effects matter most in your plan.

Depending on the cancer and treatment goal, alternatives may include surgery, systemic medicines, active monitoring or symptom-focused care. For some prostate cancers, Prostate Removal Surgery may be discussed alongside radiation options.

Look for a service where a radiation oncologist, medical physicist, radiographers and oncology nurses can coordinate planning and support. Bring a list of medicines, prior treatments and questions about transport, symptoms and follow-up.