A trial looking at radiotherapy during surgery for cancer of the rectum

This trial is looking at a new type of radiotherapy that you have during surgery for cancer of the back passage (rectal cancer). Doctors call this intra operative radiotherapy. This trial is for people under the care of Ninewells Hospital in Dundee.

Doctors usually treat rectal cancer with surgery. You may also have a course of rectal radiotherapy before surgery, to shrink the cancer enough to remove it. Or you may have radiotherapy after surgery, to help stop the cancer coming back. Although this type of radiotherapy works very well, you may have side effects later in life. This is because the radiotherapy beam may affect some healthy tissue surrounding the treatment area.

To help stop this happening, you may instead be able to have radiotherapy during surgery to remove your cancer. This is called ‘intra operative radiotherapy’ or ‘IORT’. The beam can be aimed directly into the cancer, rather than having to shine through skin and any body tissue that may be in the way. Results so far suggest that this treatment may work well. But unfortunately, it is not practical in a lot of hospitals.

This trial is looking at a new type of intra operative radiotherapy called the ‘photon radiosurgery system’, or PRS. The machinery is much smaller, and uses low energy X-rays. So it can be used in a standard operating theatre. The hospital running the trial already uses it to treat breast cancer and brain tumours. Researchers at the hospital believe that this treatment may also work well for rectal cancer.

The researchers in this trial will also look at tissue removed during surgery to see how the radiotherapy affects rectal cancer cells and healthy cells. This may help them understand more about why some people respond better to radiation than others. The aims of this trial are to

Find out about the safety of PRS and see how well it works
To learn about the effects of PRS on cancer tissue and healthy tissue

Recruitment

Start 01/01/2010

End 30/01/2013

Phase

Phase 1

Who can enter

You can enter this trial if you

Are under the care of Ninewells Hospital in Dundee
Have cancer of the back passage (rectum)
Are well enough to have surgery aimed to cure your rectal cancer (radical surgery)

You cannot enter this trial if you

Need to have a long course of chemotherapy with radiotherapy (chemoradiation) to make your cancer small enough to be removed with surgery
Have cancer that has spread (metastasised) to distant parts of your body

Trial design

This phase 1 trial will recruit 25 people. If this trial shows this treatment is safe, it will go on to be tested in a larger randomised trial comparing it with standard radiotherapy for rectal cancer.

Everyone taking part will have their planned surgery to remove their cancer. But instead of having 5 days of radiotherapy before your surgery, you will have radiotherapy during your surgery.

Before the surgeon removes your cancer, the surgeon and radiotherapy doctor (radiotherapist) will place the X-ray probe into the cancer and give you a dose of radiotherapy. They will then remove the cancer, and treat the tissue where the cancer was (the ‘tumour bed’) with a second dose of radiotherapy. The surgeon then completes your operation in the usual way.

The trial team want to find the best dose of radiotherapy to give like this. You will have one of 2 possible doses in this trial. Both work well to treat rectal cancer when used in standard radiotherapy. The dose you have will be decided by chance (randomly). Neither you nor your doctor will be able to decide which dose you have.

The surgeon will also take small samples of tissue (biopsies) from the cancer and nearby healthy tissue before and after the first dose of radiotherapy. And a sample from the tumour bed before and after this area is treated. The team will look at these samples to see how the tissue was affected by radiotherapy.

You will also give a blood sample before and after your operation.

Hospital visits

You will have radiotherapy during your surgery. The radiotherapy and biopsies for the trial will add about an hour to your surgery.

You will have fewer hospital visits by taking part in this trial. This is because you would otherwise visit the hospital for a number of radiotherapy treatments before your operation.

After your surgery, you will attend follow up appointments in the out patients clinic, in the usual way. The trial team will meet with you when you come to the hospital for your routine clinic appointments, to see how you are getting on. They will follow your progress for at least 5 years.

Side effects

As with any new treatment, the doctors may not know of all the possible side effects. This is one of the reasons for the trial. But specialists using this treatment for breast and brain cancer have not yet had any problems. The trial team believe this treatment may even have fewer side effects that standard radiotherapy.

This treatment will mean that you are under anaesthetic for an extra hour. Your surgical team will consider this when they decide whether you are fit to have surgery in the first place.