External radiotherapy for nasopharyngeal cancer

External radiotherapy usually uses high energy x-rays to kill cancer cells. A large machine aims the x-ray beams at the cancer. 

You usually have a form of external radiotherapy called intensity modulated radiotherapy (IMRT).

IMRT shapes the radiotherapy beams to the cancer and different doses of radiotherapy can be given to different parts of the treatment area. This means the healthy tissue around the cancer gets lower doses of radiotherapy. This helps to reduce the risk of side effects.

How do you have external radiotherapy?

You have your treatment in the hospital radiotherapy department.

You go to the hospital for treatment once a day, from Monday to Friday, with a break at the weekends. The length of the course of treatment varies but it is usually between 4 and 7 weeks.


If you smoke, your doctor will advise you to give up before you start treatment. Radiotherapy might not work as well and you may have more side effects if you continue to smoke.

The radiotherapy room

Radiotherapy machines are very big and could make you feel nervous when you see them for the first time. The machine might be fixed in one position or able to rotate around your body to give treatment from different directions. The machine doesn't touch you at any point.

Before your first treatment, your therapy radiographers Open a glossary item will explain what you will see and hear. In some departments the treatment rooms have docks for you to plug in music players. So you can listen to your own music while you have treatment.

Photo of a linear accelerator

It is important to lie in the same position each time, so your radiographers may take a little while to position you on the couch. You have a mask around your face to keep your head still, which they attach to the couch. They make sure your mask feels comfortable.

Once you are in the right position they leave you alone in the room.

During the treatment

You need to lie very still. The machine makes whirring and beeping sounds. You won’t feel anything when you have the treatment.

Your radiographers can see and hear you on a CCTV screen in the next room. They can talk to you over an intercom. They will ask you to raise your hand if you need anything but it is important to stay as still as possible. 

The treatment can take between 15 to 30 minutes.

You won't be radioactive

This type of radiotherapy won't make you radioactive. It's safe to be around other people, including pregnant women and children.

Stereotactic radiotherapy

Stereotactic radiotherapy is another form of external radiotherapy you might have for nasopharyngeal cancer.

This gives radiotherapy from many different angles around the body. All the radiation beams meet where the cancer is. So the cancer gets a very high dose of radiation and the areas around it get a much lower dose. This helps to reduce side effects. You may have this treatment in a single session.

You are more likely to have stereotactic radiotherapy for nasopharyngeal cancer that has come back near to where it started (local recurrence).

Travelling to radiotherapy appointments

You might have to travel a long way each day for your radiotherapy. This depends on where your nearest cancer centre is. This can make you very tired, especially if you have side effects from the treatment.

You can ask the therapy radiographers Open a glossary item for an appointment time to suit you. They will do their best, but some departments might be very busy. Some radiotherapy departments are open from 7am till 9pm.

Car parking can be difficult at hospitals. Ask the radiotherapy staff if you are able to get free parking or discounted parking. They may be able to give you tips on free places to park nearby.

The radiotherapy staff may be able to arrange transport if you have no other way to get to the hospital. Your radiotherapy doctor would have to agree. This is because it is only for people that would struggle using public transport and have no access to a car. 

Some people are able to claim back a refund for healthcare travel costs. This is based on the type of appointment and whether you claim certain benefits. Ask the radiotherapy staff for more information about this.

Some hospitals have their own drivers and local charities might offer hospital transport. So do ask if any help is available in your area.

Side effects

Last reviewed: 
16 Feb 2021
Next review due: 
16 Feb 2024
  • External Beam Therapy
    P Hoskin
    Oxford University Press, 2019

  • Nasopharyngeal carcinoma: ESMO-EURACAN Clinical Practice Guidelines for diagnosis, treatment and follow-up
    P Bossi and others
    Annals of Oncology, 2021. Volume 32, Issue 4, Pages 452 - 465

  • Nasopharyngeal carcinoma: United Kingdom National Multidisciplinary Guidelines
    R Simo and others
    The Journal of Laryngology and Otology, 2016. Volume 130, Supplement 2, Pages 97-103

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