A trial looking at increasing the dose of radiotherapy for bowel cancer (OPERA)

Please note - this trial is no longer recruiting patients. We hope to add results when they are available.

Cancer type:

Bowel (colorectal) cancer

Status:

Closed

Phase:

Phase 3

This trial is comparing 2 ways of giving an increased dose of radiotherapy before surgery for rectal cancer. It is open to people with cancer of the back passage (rectum) that can be removed by surgery.

More about this trial

The standard treatment for rectal cancer is to have surgery to remove the rectum.

Another treatment doctors might use is chemoradiotherapy. You have 5 weeks of radiotherapy to the area between your hips (pelvis) along with a chemotherapy tablet twice a day.

After chemoradiotherapy if there is no sign of the cancer (a complete response) you might not need to have surgery. Or if you still need surgery it might not mean removing the rectum. Unfortunately after chemoradiotherapy a complete response is rare.

Studies have shown that increasing the amount of radiotherapy can increase the chances of a complete response. This can be done by giving extra doses of radiotherapy after the 5 weeks. This is called a boost.

In this trial researchers want to compare 2 ways of giving a boost of radiotherapy:

using external radiotherapy
using internal radiotherapy (brachytherapy)

The aims are to:

find out if giving a boost of radiotherapy after the initial 5 weeks can increase the chances of getting a complete response
find out which is the best way of giving the boost
find out what are the side effects
compare the quality of life

Who can enter

The following bullet points list the entry conditions for this trial. Talk to your doctor or the trial team if you are unsure about any of these. They will be able to advise you.

You may be able to join this trial if all of the following apply. You:

have a type of rectal cancer called adenocarcinoma that is stage T2, T3a or T3b
have cancer that is less than 5cm across and has spread to at least1 lymph node and no more than 3 lymph nodes. If your cancer has spread to the lymph node, it must be less than 8mm across
can have surgery to remove the cancer
can have internal radiotherapy (brachytherapy) to the cancer
are willing to use reliable contraception during treatment
are at least 18 years old

You cannot join this trial if any of these apply. You:

are not able to have surgery to remove the cancer
have cancer that has grown through the outer lining of the rectum or has spread to another part of the body
have cancer that has spread to 4 or more lymph nodes. Or it has spread to 1 to 3 lymph nodes and any of the lymph nodes is 8mm or more across
have cancer that is high grade
have had radiotherapy to the area between your hips (pelvis)
are not able to have radiotherapy
have cancer that has grown into the ring of muscle around your anus (anal sphincter)
have another cancer that is continuing to get worse
have another medical or mental health condition that might affect you taking part in this trial
have taken an experimental drug or used an experimental device as part of another clinical trial in the past 28 days
are pregnant or breastfeeding

Trial design

This is an international European phase 3 trial. The team need 236 people in Europe to join the trial, 120 from the UK.

Everyone has chemoradiotherapy followed by a boost (extra doses) of radiotherapy. For chemoradiotherapy you have capecitabine at the same time as your radiotherapy.

Capecitabine is a tablet you take twice a day when you have radiotherapy.

You have 5 weeks of radiotherapy Monday to Friday.

The boost part of the trial is randomised. You are put into 1 of 2 groups by a computer. Neither your or your doctor can choose which group you are in.

Everyone taking part has chemoradiotherapy followed by one of the following:

5 extra doses of external radiotherapy
3 extra doses of internal radiotherapy

OPERA diagram

During the 14th week after starting chemoradiotherapy your doctor will assess how well the cancer has responded to treatment. The response can be either:

no sign of the cancer (complete response) or almost complete response
the cancer has shrunk (partial response)
the cancer has stayed the same (stable disease)
the cancer has got worse (progression, which is very rare)

Whether you need further treatment depends on the response. Your doctor will talk to you about this.

For a complete response or almost complete response
You might have:

regular follow up only
surgery to remove the rectum
surgery through the anus to remove the remaining cancer (local surgery)

For partial response and stable disease
It is recommended you have surgery to remove the rectum. You have the surgery about 3 weeks after seeing the doctor for the assessment.

Quality of life
You fill in a quality of life questionnaire:

before starting treatment
3 months after finishing treatment
every 3 months for a year
every 6 months for 2 years

The questions ask you about:

your general health
any side effects you might have

Hospital visits

You see the doctor before taking part to have the following tests:

a physical examination
heart trace (ECG)
rectal examination
sigmoidoscopy (a test to look at the lower end of the bowel)
blood tests
MRI scan
CT scan

During treatment you see the doctor every week to see how you are. People having the 3 extra doses of internal radiotherapy also have a rectal examination during their boost.

You see the doctor 14 weeks after starting treatment to assess how well the cancer responded to treatment. And to talk about further treatment.

You then see the doctor:

every 3 months for a year
then every 6 months for 2 years

Side effects

The most common side effects of radiotherapy are:

sore or inflamed skin around the bottom and anus, this usually happens about 3 to 4 weeks of having treatment
pain when having a poo (faeces)
diarrhoea
pain when passing urine
women might have irritation in their vagina
tiredness and drowsiness

The most common side effects of capecitabine are:

diarrhoea
a drop in the amount of blood cells making you at higher risk of getting an infection, tiredness, bruising and bleeding
tingling, numbness, swelling, redness or pain of the hands and feet (hand-foot syndrome)

Your doctor will talk to you about the side effects of treatment before you agree to take part.

We have information about the side effects of radiotherapy for rectal cancer and capecitabine.