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Radiotherapy treats cancer by using high-energy x-rays to destroy cancer cells, while doing as little harm as possible to normal cells. The treatment is given in the hospital radiotherapy department.
Radiotherapy is usually given by aiming high-energy x-rays at the lung from a radiotherapy machine. This is known as external beam radiotherapy. Some people with small cell lung cancer are given radiotherapy to the brain.
The number of treatments you have, and the length of time they take, will depend on the stage| of the cancer and the aim of the treatment.
Radiotherapy is sometimes used to treat limited stage small cell lung cancer.
It may be given following chemotherapy (adjuvant radiotherapy) if the cancer has shrunk a lot or disappeared after the chemotherapy. Sometimes radiotherapy is given at the same time as the chemotherapy. This is called chemoradiation. The radiotherapy and chemotherapy treatment can help to stop small cell lung cancer coming back and may help to completely remove any signs of the cancer for some people.
Treatment is usually given every day with a rest at the weekends over 3–6 weeks.
There is a risk that small cell lung cancer can spread to the brain, so your doctor may recommend that you have radiotherapy to the brain. This may help to stop the cancer from spreading to this area.
Radiotherapy can also be used to control and relieve symptoms such as breathlessness, chest pain, a cough and coughing up blood. This is called palliative radiotherapy. In this case, only one or two treatments are given. But a higher dose of radiotherapy over two weeks can be given if the doctor thinks this may be helpful. Treatment is given each weekday with a rest at the weekend.
To make sure that the radiotherapy works as well as possible, it has to be carefully planned. Before you start your treatment you'll have pictures taken with a special CT scanner| and measurements taken by the radiographers. This information will be used to work out the details of your radiotherapy. Treatment planning is a very important part of radiotherapy, and it may take a couple of visits. The doctor who plans and supervises your treatment is known as a clinical oncologist.
Marks may be drawn on your skin to help the radiographer, who gives you your treatment, to position you accurately and to show where the rays are to be directed. It’s important not to wash or rub them off until the treatment is finished. Occasionally, tiny permanent marks (tattoos) are made on the skin in case further treatment is needed later. At the beginning of your radiotherapy you'll be given instructions on how to look after your skin in the area to be treated.
Before each session of radiotherapy the radiographer will position you carefully on the couch, either sitting or lying, and make sure that you're comfortable.
Positioning the radiotherapy machine
View a large copy of the diagram showing the positioning of the radiotherapy machine|
During your treatment you will be left alone in the room, but you'll be able to talk to the radiographer who will be watching you. Radiotherapy is not painful and only takes a few minutes, but you do have to stay still while the treatment is being given.
Some people with small cell lung cancer are given radiotherapy to the brain. This is because there is a risk that the cancer cells will spread here. Giving radiotherapy in this way is called prophylactic cranial radiotherapy (PCR)| or prophylactic cranial irradiation (PCI).
A soft clamp is used to hold your head still to make sure that the correct area of your head is treated. Sometimes a see-through plastic mask or mould is made to help keep your head in the right position during treatment.
PCR is usually given daily, Monday to Friday. The number of sessions will vary depending on the individual situation.
Radiotherapy can cause general side effects, such as tiredness. It can also cause chest pain or a few days of flu-like symptoms. You may notice that you develop a cough and produce more sputum (phlegm), which may have flecks of blood in it. This is quite normal. These side effects can be mild or more troublesome, depending on the strength of the radiotherapy dose and the length of your treatment. Your doctors or radiographers will be able to advise you about what to expect.
After 2–3 weeks of treatment, the main problem you're likely to notice is difficulty swallowing. This may be very uncomfortable. You may also have heartburn and indigestion. This happens because the radiotherapy can cause inflammation in your gullet (oesophagus).
Tell your doctors if you have problems swallowing, as they can give you medicines to help. If you don’t feel like eating, or have problems with swallowing, you can replace meals with nutritious, high-calorie drinks. These are available from most chemists and can be prescribed by your GP.
Our section on diet| has some helpful hints on how to eat well when you are feeling ill.
Radiotherapy can make you feel tired|, so try to get as much rest as you can, especially if you have to travel a long way for treatment each day.
Some people develop a skin reaction similar to sunburn. Pale skin may become red and sore or itchy; darker skin may develop a blue or black tinge. Your radiographers will give you advice on how to look after your skin.
This will only happen within the treatment area, so will include chest hair for men or head hair if you are given prophylactic cranial radiotherapy. The hair usually grows back, although occasionally the hair loss| is permanent.
Any side effects should disappear gradually once your treatment is over, but it’s important to tell your doctor if they continue.
Radiotherapy treatments for lung cancer do not make you radioactive. It's perfectly safe for you to be with other people, including children, throughout treatment.
Very rarely radiotherapy for lung cancer can cause long-term side effects such as inflammation, or hardening and thickening (fibrosis) of the lungs. This can cause symptoms such as shortness of breath and a cough. The gullet (oesophagus) may also be affected and become narrower, making swallowing difficult. The bones in the chest area may become thinner and more brittle.
Long-term side effects are very rare, but it’s important that you are aware of them so that you can seek medical advice if you notice any symptoms.
Our radiotherapy section| tells you more about this treatment and its side effects.
For answers, support or just a chat, call the Macmillan Support Line free (Monday to Friday, 9am-8pm)
If you have any questions about cancer, need support or just want someone to talk to, ask Macmillan.