A trial to learn more about genetic differences in cancer of the back passage (MARVEL)

Cancer type:

Bowel (colorectal) cancer
Rectal cancer




Phase 2

This trial is looking at tissue samples from people who have cancer of the back passage (rectum) and are having a combination of chemotherapy and radiotherapy (chemoradiation) followed by surgery. The trial aims to learn about gene differences in this cancer.

Treatment for cancer of the back passage (rectal cancer) has greatly improved over the years. But it is important for doctors to find out as much as they can about the tumours so that they can develop new treatments.

It may be possible to improve current treatments by learning more about rectal cancer genes. Genes are coded messages that tell cells how to behave. They control growth and development of the body. But if a gene is changed (mutated) it can make the cell stop working properly and become cancerous.

Doctors in this trial hope to identify genetic Open a glossary item differences in certain types of rectal cancer. They will recruit people with rectal cancer who are having chemoradiation Open a glossary item and surgery. If you take part you will give the team permission to study tissue removed when you were diagnosed (biopsy), and during surgery. The aim of this trial is to identify genetic differences in certain types of rectal cancer, which may one day help improve treatment.

Who can enter

You may be able to enter this trial if you

  • Have a type of rectal cancer called adenocarcinoma Open a glossary item of the rectum
  • Are due to have a combination of chemotherapy and radiotherapy before surgery to treat your cancer
  • Are at least 18 years old

You cannot enter this trial if

  • You cannot have an MRI scan for any reason, such as feeling very uncomfortable in small spaces, or having metal or a pacemaker Open a glossary item in your body
  • You have a rare form of an eye condition called glaucoma that causes the pressure in your eye to rise very quickly (closed angle glaucoma), or a muscle weakness condition called myasthenia gravis – both mean that you can’t have a drug called buscopan
  • Your kidneys are not working well enough to remove the MRI contrast dye from your body
  • You are allergic to the MRI contrast injection gadolinium
  • You would not be able to have a bowel contrast drink for any reason
  • You end up having emergency surgery to treat your cancer, so would not have a chance to have the pre surgery MRI scan

Trial design

This trial will recruit 160 people. Everyone will have an MRI scan before their rectal cancer surgery as planned.

As well as looking at the samples you give, the researchers are looking at how well an MRI scan shows how far rectal cancer has spread. The hospital laboratory will look at the bowel cancer that was removed, to confirm how far it has spread. This is routine. The trial team will then compare this information with that from the MRI scan. This is to see how accurate the MRI scan was in showing how far your cancer had spread before you had surgery.

They will also collect some information about you from your medical notes. They will treat this information confidentially Open a glossary item, so no one will be able to link the results to you.

Hospital visits

You will not need to make any extra hospital visits to take part in this trial.

Side effects

You will not have any side effects as a result of taking part in this trial.


Burton on Trent
Sutton in Ashfield

Recruitment start:

Recruitment end:

How to join a clinical trial

Please note: In order to join a trial you will need to discuss it with your doctor, unless otherwise specified.

Please note - unless we state otherwise in the summary, you need to talk to your doctor about joining a trial.

Chief Investigator

Prof Gina Brown

Supported by

Institute of Cancer Research (ICR)
NIHR Clinical Research Network: Cancer
Pelican Cancer Foundation
Royal Marsden NHS Foundation Trust

Questions about cancer? Contact our information nurses

Freephone 0808 800 4040

Last review date

CRUK internal database number:


Please note - unless we state otherwise in the summary, you need to talk to your doctor about joining a trial.

Over 60,000 cancer patients enrolled on clinical trials in the UK last year.

Last reviewed:

Rate this page:

No votes yet
Thank you!
We've recently made some changes to the site, tell us what you think

Share this page