Cancer treatment: what happens during radiotherapy? 

See what happens during radiotherapy treatment. An expert describes what happens and advises what questions to ask if you're referred for radiotherapy.

Find out more about radiotherapy

Transcript of Cancer treatment: what happens during radiotherapy?

I'm Dr Michael Williams.

I'm a consultant clinical oncologist at Addenbrooke's Hospital in Cambridge.

If I were a patient who'd been referred for radiotherapy,

the things that I would want to ask my doctor

would be first of all things about the illness itself,

the disease, its extent

and whether or not it's curable with treatment.

I would then want to know details about the radiotherapy treatment itself

and the procedures involved.

And then I think the next thing would be the side effects,

both in the short term and long term,

and overall the chance of success and what the aims of treatment are.

Radiotherapy is a treatment with radiation

and the radiation is produced from an x-ray machine

and comes out as a beam that can be neither seen nor felt.

It's quite painless to have and is able to damage cancer cells,

although it also damages normal cells,

but the normal cells can recover from the injury much better

whereas the cancer cells go on and die,

so it has a high success rate in treating cancer

in the area that it's shone at.

The radiotherapy process starts with an appointment to see the consultant,

who will discuss the disease that's going to be treated,

what the outlook is,

and will outline the next steps and the side effects from radiotherapy.

This usually involves a patient having a full explanation and signing consent.

Courses of treatment depend on what the intention is.

For palliative treatment,

which is to relieve symptoms in patients who have an incurable disease,

it may be a short course of treatment over a week or a single attendance.

For radical treatment which aims to cure the patient,

it will usually go on for four to six or seven weeks.

This will involve attending every day

and the patient will be in the room on the treatment machine

for about ten minutes.

The beam is usually on for a small proportion of that,

so each field, of which there may be three or four fields,

will be on for about a minute.

At that point, all the staff leave the that room so they don't get irradiated,

the beam comes on, there's a little bit of a whirring and buzzing,

the patient doesn't feel anything,

then the staff come back in and set up the next treatment field.

Radiotherapy treatment itself doesn't hurt.

You can't tell when it's on in terms of sensation.

You can hear the machine making a whirring noise

but you don't feel anything at the time.

But it may be unpleasant in that it produces side effects.

Patients can feel sick afterwards so they're given anti-sickness drugs,

and depending what part of the body is being treated

there will be other side effects during treatment,

possibly sore skin, possibly diarrhoea.

Those would have to be discussed with your consultant before treatment.

The long-term risks vary

and you would need a detailed conversation with your consultant

about what the hazards are.

One of the important hazards for all patients

is the risk that radiotherapy may induce a second cancer.

That is rare but an important complication

which should be discussed with the patient.

Whether or not radiotherapy is given in combination

would depend on the disease being treated.

For some cancers, such as head and neck cancer,

it can be the only treatment and then replaces surgery.

For other diseases, such as breast,

cancer it's used in combination with surgery

so that the main lump is removed by surgery

and then radiotherapy follows.

And for other diseases which are sensitive to chemotherapy,

such as lymphoma, chemotherapy is given first

and then radiotherapy is used to consolidate at the end.

People you'd expect to meet

are first of all the doctor who is the clinical oncologist or radiotherapist

in charge of your treatment.

Other people involved would be radiographers

who would actually use the scanning machine,

which is part of planning your treatment.

They would deliver your treatment on a daily basis.

The third group are the physicists,

who measure the output from the machine

and do all the calculations to do with producing the plan

which is individualised for you,

of how long the machine has to be on in order to give the correct dose.

Radiotherapy is one of the main ways in which we can cure cancer.

It comes second only to surgery

and contributes to curing just under half the patients

who are cured of their cancer.


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