A study looking at a test to examine lymph nodes during surgery for women’s cancers (PIONIR)

Cancer type:

Cervical cancer
Vulval cancer
Womb (uterine or endometrial) cancer





This study used a dye and a special camera to find the first lymph node that cancer might have spread to for women’s cancers (gynaecological cancer).

The first lymph node Open a glossary item that cancer cells in lymphatic fluid reach is called the sentinel node.

Cancer Research UK supported this study.

More about this trial

This study started in 2012 and the results were published in 2015.

The aim of the study was to see if a dye that shows up under a special camera helped surgeons to see the lymph nodes nearest the cancer during surgery for women’s cancers.

Cancer cells can spread to lymph nodes. The surgeon might remove all the lymph nodes closest to the cancer during surgery. A specialist doctor (pathologist Open a glossary item) looks at them after surgery to find out if they contain cancer. Often, they don’t contain cancer cells but the surgeon removes them just in case.

Removing all the nodes can increase the risk of side effects or complications. So, knowing if nearby lymph nodes contain cancer could mean that surgeons would only need to remove those affected.

In this study, the surgeon injected a dye into the cancer during surgery. This dye glowed under infrared light and showed the surgeon the sentinel nodes.

The researchers hoped this would mean surgeons could test sentinel nodes for cancer during surgery.

Summary of results

The study team found that the dye and camera helped to find the sentinel nodes during routine surgery for women’s cancers.

49 women took part in this trial. They all had routine surgery for women’s cancer. During surgery, the surgeon:

  • injected the dye and used the camera to find the sentinel lymph nodes
  • removed all nearby lymph nodes as was standard practise at the time

They sent all the removed lymph nodes and sentinel nodes to the pathologist to check for cancer cells. The areas that glowed under the camera were called ‘hotspots’.

The study team found:

  • early in the study, some hotspots weren’t lymph nodes but were fatty tissue
  • after a learning phase (30 women), surgeons were able to obtain sentinel nodes using this method in the rest of the women
  • all the sentinel nodes that contained cancer correctly predicted if the other lymph nodes would contain cancer
  • about 2 out of 10 (20%) of the lymph nodes contained cancer cells

16 women had the highest possible dose of the dye. The researchers called this the optimised dose. In these women, the hotspots were 100% accurate at finding the sentinel node.

Side effects
There weren’t any side effects because of having the dye injected.

The study team concluded that it was possible to use the dye and camera to correctly identify sentinel nodes during surgery for women’s cancers. They plan to test this method in a larger group of women. 

We have based this summary on information from the research team. The information they sent us has been reviewed by independent specialists (peer reviewed Open a glossary item) and published in a medical journal. The figures we quote above were provided by the trial team who did the research. We have not analysed the data ourselves.

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 Ahmed Ahmed

Supported by

Cancer Research UK
Engineering and Physical Sciences Research Council (EPSRC)
Experimental Cancer Medicine Centre (ECMC)
Oxford Cancer Imaging Centre
University of Oxford

If you have questions about the trial please contact our cancer 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