A trial looking at a new device to help surgeons know if they have removed all the breast cancer (REI-EXCISE)

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

Cancer type:

Breast cancer





This trial is looking at a device called the intelligent Knife or iKnife. They want to find out if it can help surgeons know if they have removed all of the cancer, during breast cancer surgery.

It is for people who are going to have surgery to remove an area of cancer from the breast. This is often called:

  • lumpectomy
  • wide local excision
  • breast conserving surgery

Cancer Research UK supports this trial.

More about this trial

During a lumpectomy, the surgeon removes the area of breast cancer and an area of normal tissue around it. They leave behind as much normal tissue as possible. 

After the operation, a pathologist Open a glossary item looks at the tissue removed. They check the border of tissue around the tumour for cancer cells. The pathologist says that you have clear margins if there are no cancer cells at this border. They say it’s a positive margin if there are cancer cells at this border.  

The risk of the cancer coming back is lower if you have clear margins after surgery. So, you might need more surgery to take more tissue away if there are positive margins after lumpectomy.  

Surgeons would like to know during surgery if they have removed all of the cancer and the margins are clear. So that it reduces the need for another operation. In this trial, they are looking at a new device called intelligent knife (iKnife). 

The iKnife works in the same way as the standard surgical tools. But it catches the substances produced during surgery (smoke) and passes it through a machine. The machine then tells the surgeon if they are removing healthy or cancer tissue. 

The aim of this trial is to find out if surgeons can use the iKnife during surgery to check that they have removed all of the cancer. 

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. 

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

Who can’t take part
You cannot join this trial if any of these apply. You:

Trial design

Researchers need about 175 people to take part. 

You have surgery on the same way as you would if you weren’t taking part in this trial. Your doctor can tell you what happens during the operation. 

During surgery, doctors use the iKnife to analyse the substances produced (smoke). They then compare these results with the pathologist report. 

The surgical team makes a video during the operation. This is so doctors know which part of the breast they removed when they look at the iKnife results. Only members of the research team will look at the video. And no one will be able to identify you.  

Hospital visits

You see a doctor before the operation. They look at your medical history Open a glossary item and the information about your breast cancer. 

You have surgery as planned. Doctors send any cancer and healthy tissue removed to the pathologist. This is the same as the standard treatment. 

After a lumpectomy, you usually go home the same day, or occasionally the day after surgery. The trial team doesn’t think you need to stay in hospital any longer than normal, if you take part in this trial. 

About 2 out of every 10 people (20%) need more surgery afterwards. Your doctor might ask you to continue in this trial if this happens. 

Side effects

The trial team doesn’t think you will have any side effects from using the iKnife during the operation.

The team will tell you about all the possible side effects of a lumpectomy.

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

Professor Zoltan Takats
Mr Daniel Richard Leff

Supported by

Cancer Research UK
Imperial College Healthcare NHS Trust
Imperial Clinical Trials Unit - Cancer (ICTU-Ca)

Other information

This is Cancer Research UK trial number CRUK/16/021

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.

Harriet wanted to try new treatments

A picture of Harriet

“I was keen to go on a clinical trial. I wanted to try new cancer treatments and hopefully help future generations.”

Last reviewed:

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