Radiation can be given externally or internally. The treatment you will receive depends on the type and stage of the disease as well as the location.
Most people who receive radiation therapy for cancer have external beam radiation. The beams are generated in a machine called a linear accelerator. The machine directs the high energy x-rays at the cancer, treating that and a small margin of normal tissue around the edge of the treatment field.
When internal radiation therapy is used, the radiation source is placed inside the body. This method of radiation is called brachytherapy.
Some patients have both forms of radiation, one after the other.
What does treatment planning mean?
Before starting with the actual radiotherapy treatment, the precise location of the area to be radiated must be determined. Your radiation will be planned specifically for you as an individual in order to deliver the maximum amount of radiation to the cancer mass while limiting the dose to the surrounding normal tissues to the minimum.
You will be asked to lie very still on a treatment couch while a radio therapist will use a special x-ray machine, the simulator, to define your treatment field. Depending on the location of your cancer, single or multiple treatment fields may be necessary. The planning process may also involve a CT scan of the affected area in order to plan radiation fields more accurately by taking different tissue densities into account. After completion of the CT scan it may take another day or two to develop a final treatment plan, a process during which different radiation combinations and options are considered in order to determine the best possible treatment plan for every individual patient.
Small tattoos in the form of pinpointed dots will be placed on your skin to define the treatment area. This is to ensure that treatment is delivered to exactly the same area every day; the tattoos also enable one to determine areas where radiation has been delivered previously, even years after treatment. Non-permanent pen marks will also be used to ease daily setup and treatment field determination.
Before your first treatment a set of special x-rays will be taken. This is to again confirm that the radiation will be delivered to the correct area; it also serves as a record of your treatment. These x-rays are often repeated during your course of radiotherapy to verify their correctness.
How long does treatment last?
Most cancers are treated with radiotherapy for 5 days per week over a 6 to 7 week period. (When radiation is given for symptom control only, shorter treatment periods are used, which could be from a few days up to 3 weeks.) Every treatment lasts 10 tot 20 minutes, the actual radiation therapy takes only a few minutes per day, while setting you up in the correct position, and adjustments between various radiation fields make up for the remainder of the time.
The use of smaller daily doses of radiation given over a longer period of time instead of a few large doses over a shorter time period helps to protect normal tissue in the treatment area. Rest periods over weekends also help normal cells to recover from the radiotherapy.
What happens during radiation treatments?
Wearing clothes that are easy to take off and put on is advisable.
The radiotherapist will use the marks on your skin to position you correctly and to determine the treatment field. You will be asked to lie very still on the treatment couch; although you will be alone in the room during the treatment, continuous monitoring through a closed circuit camera system will be done. External beam radiation is painless, and is comparable to x-rays taken for diagnostic purposes. You will not see or smell the radiation. You may hear a sound whilst the radiation beam is running, this is normal. The radiation will not make you radioactive. After starting treatment, your doctor will monitor your treatment progress as well as your reactions to treatment.
You need to remain very still during the treatment so that the radiation reaches only the area where it’s needed and the same area is treated each time.
You don’t have to hold your breath – just breathe normally. The radiation machine is controlled from the control area nearby. You will be watched on a television screen from the control room. There is also an intercom system. If you should feel ill or very uncomfortable during the treatment, tell your therapist at once. The machine can be stopped at any time and treatment restarted without any bad effects on the treatment.
What are the side effects of treatment?
External radiation therapy does not cause your body to become radioactive. There is no need to avoid being with other people because you are undergoing treatment. Even hugging, kissing, or having sexual relations with others pose no risk of radiation exposure.
Most side effects of radiation therapy are related to the area that is being treated. The side effects of radiation therapy, although unpleasant, are usually not serious and can be controlled with medication or diet. They usually go away within a few weeks after treatment ends.
Depending on the area being treated, you may need to have routine blood tests to check different levels as radiation treatment can cause decreases in the levels of different blood cells.
What can I do to take care of myself during therapy?
Each patient’s body responds to radiation therapy in its own way.
Some general guidelines:
- Before starting treatment, be sure your doctor knows about any medicines you are taking and if you have any allergies
- Your body will use a lot of extra energy over the course of your treatment, and you may feel very tired. Be sure to get plenty of rest and sleep as often as you feel the need. It’s common to feel tiredness for 4 to 6 weeks after your treatment has been completed
- Good nutrition is very important. Try to eat a balanced diet that will prevent weight loss
- Check with your doctor before taking vitamin supplements or herbal preparations during treatment
- Avoid wearing tight clothes over the treatment area
- Be extra kind to your skin in the treatment area:
- Wear loose, soft cotton clothing over the treated area
- Do not scratch, rub, or scrub treated skin
- Do not use adhesive tape on treated skin. If bandaging is necessary, use paper tape and apply it outside of the treatment area
- Use only lukewarm water for bathing the area
- Use an electric shaver if you must shave the treated area. Do not use a pre-shave lotion or hair removal products on the treated area
- Protect the treatment area from the sun. Do not apply sunscreens; cover treated skin (with light clothing) before going outside
- Ask your doctor about washing the affected area as no scented or coloured soaps or talcum powder should be used (non perfumed and glycerine soaps are available and Maizena is a good substitute for talc).