Radiotherapy, like chemotherapy, is a form of cancer treatment that uses X-rays to cure or control cancer cells. It's a safe and mostly painless practice, though it does often come with some side effects.
Dr Roger Henderson explains how radiotherapy works, why it's beneficial, and what the potential side effects of X-ray related cancer treatment are:
What is radiotherapy?
Radiotherapy is a form of cancer treatment that uses high energy X-rays to destroy or injure cancer cells so they cannot multiply. Radiotherapy can be used to treat either primary cancers or advanced cancer where the cancer has spread to other parts of the body.
Some of the normal cells of the body can also be damaged by radiotherapy treatment, but they are better at repairing themselves than cancer cells, so tend to recover.
How is radiotherapy given?
Many people with different types of cancer have radiotherapy as part of their treatment and there are a number of ways it can be given.
These include administering it from outside the body (external beam) – where a machine directs radiation at the cancer and surrounding tissue, or from inside the body (brachytherapy) where radioactive material is put in thin tubes and placed in your body near the cancer.
There is also radioisotope therapy, when you are given an injection, drink or capsule. Radiotherapy may be given by itself only as the only treatment used in treating a particular cancer, or it can be given in combination with surgery and/or chemotherapy.
Radiotherapy can also be used to reduce the size of a cancer and help to reduce pain, discomfort or other symptoms.
Why is radiotherapy given?
The three main reasons for using radiotherapy are:
Some cancers can be cured by radiation therapy alone or combined with other treatments, whereas others cannot be cured, but can be controlled by making them smaller or stopping them from spreading.
For symptomatic relief - when a cure is not possible - radiotherapy may be used to reduce symptoms and improve quality of life.
How long is a course of radiotherapy treatment?
This depends on what sort of cancer is present, where it is, its size, the general health of a patient and other cancer treatments they may have had.
Some people need only one treatment, whereas others need radiation therapy five days a week for several weeks. If internal radiation therapy is used then the implants may be left in place for either a few minutes or one to six days or permanently.
Does radiotherapy hurt?
External radiotherapy does not hurt. It is important to know that anyone having this type of radiotherapy will not be radioactive and it is safe to be in with other people, including pregnant women and children either before or after treatment.
With internal radiotherapy there can be some mild discomfort from an implant, but there should be no severe pain. While a radioactive implant is in place in the body it may emit some radiation outside your body and so there will be limits on visitors during this treatment.
Radiotherapy side effects
Side effects vary enormously from person to person and also depend on which area of the body is being treated. Common side effects include:
🔹 Tiredness: It is common to feel very tired during treatment and for some time afterwards.
🔹 Nausea: Some people find that their treatment makes them feel sick and may vomit following treatment. Anti-sickness drugs will help reduce or prevent this.
🔹 Skin problems: The skin in and around the treatment area may become red, sore or itchy, typically 10–14 days after starting treatment. If this happens, creams may be prescribed.
🔹 Hair loss: This only occurs if treatment is in an area where hair grows, such as the head. Any hair loss usually grows back after treatment has finished, although for some people their hair will remain thin.
🔹 Blood changes: Radiotherapy can lower red blood cell levels, causing tiredness. On occasions, a blood transfusion may be required. During radiotherapy treatment, always tell your doctor if your temperature goes above 38°C (100.4°F), or if you feel hot, cold and shaky.
🔹 Diarrhoea: Having diarrhoea, or loose bowel motions, is common if you have treatment to the abdominal area. Always drink plenty of fluids and tell the staff at the hospital if you have diarrhoea as they can give treatment to help.
🔹 Problems with passing urine: Some patients having radiotherapy find they have to pass urine more often, and this can happen with treatment near the bladder. Drinking more fluids may help and some people find it helpful to drink cranberry juice or lemon barley water.
🔹 Sore mouth: Treatment to the head and neck can cause the mouth to become sore. Regular mouthwashes and painkillers are prescribed if needed and you should not smoke. Avoid alcoholic drinks, spicy or very hot food.
✅ The good news is that most side effects of radiotherapy can be managed effectively and will gradually disappear once treatment has finished.