A study looking at developing new tests to help diagnose and stage oesophageal squamous cancer (OSCAR)

Cancer type:

Oesophageal cancer





A study using a Cytosponge test, blood tests and tissue samples to understand more about pre cancer and cancer of the lining of the food pipe (oesophagus).

It is for people with

  • pre cancer (also called dysplasia) of the food pipe or who have a high risk of pre cancer
  • cancer of the food pipe called oesophageal squamous cell cancer (SCC)

Cancer Research UK supports this study.

More about this trial

Sometimes the cells in the lining of the food pipe (gullet or oesophagus) can change and become abnormal. This is called oesophageal squamous dysplasia.  

People with oesophageal squamous dysplasia (or who have a high risk of it) have regular tests called endoscopies to check whether they have developed cancer.

But endoscopies can be uncomfortable and can have some risks. So the researchers in this study have created a new test called a Cytosponge.

Researchers think the Cytosponge can pick up on cell changes that could develop into cancer.   

There are 2 groups in this study

  • people with oesophageal squamous dysplasia or a high risk of this
  • people with oesophageal SCC

The main aims of this study are to

  • learn more about how oesophageal squamous dysplasia develops into cancer
  • see if tests can be developed to help find cell changes (dysplasia) or cancer earlier
  • create a new staging system for people with oesophageal cancer  

Who can enter

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

There are different entry conditions depending on the group you are in.

People with oesophageal squamous dysplasia or a high risk of having it
You may be able to join this group if you are at least 18 years old and you are well enough to have an endoscopy.

If you are at high risk of oesophageal squamous dysplasia at least 1 of the following must apply. You

  • Smoke and drink alcohol (at least 26 units every week)
  • Have a family history of oesophageal squamous dysplasia (2 or more relatives with a previous history of oesophageal SCC) or other oesophageal lesion (hyperkeratosis, leucoplakia, lichen planus)
  • Have had cancer of the head and neck
  • Have a condition called tylosis (thickening of the skin in the palms of the hands and soles of the feet) – or someone in your family has
  • Have been asked by your doctor to have regular endoscopies due to oesophageal squamous dysplasia  

You cannot join this group if any of these apply. You

  • Are taking drugs to thin the blood (anticoagulants) such as warfarin, clopidogrel, heparin or tinzaparin and you can’t stop them for a few days
  • Have problems swallowing (dysphagia)
  • Have cancer in the back of the mouth (the oropharynx) that needs treatment
  • Have enlarged veins close to the lining of the food pipe that might  bleed (oesophageal varices) or a narrowing (stricture) that needs a tube (stent) to allow food and drink to pass through
  • Have had cardiac problems such as heart attack in the past 6 months

People with oesophageal SCC
You may be able to join this group if the following apply. You

  • Have just been diagnosed with oesophageal SCC
  • Are at least 18 years old 

You cannot join this group if you are taking drugs to thin the blood (anticoagulants) such as warfarin, clopidogrel, heparin or tinzaparin and you can’t stop them for a few days. 

Trial design

There are 2 groups in this study. The researchers need about 200 people to take part in both groups.

People with oesophageal squamous dysplasia or a high risk of having it
You have the Cytosponge test on the same day as the endoscopy.

The study team asks you some questions about your general health and lifestyle as well as measuring your weight and height. Then you have the Cytosponge test. 

You swallow a small capsule with a drink of water. The capsule contains a sponge, covered in gelatine, which is attached to a string.

After 7 minutes, the gelatine dissolves and the sponge can be gently removed by pulling on the string. You may have a spray to numb your throat (anaesthetic) before pulling out if needed.

As the sponge is pulled up and out of your mouth, it collects cells from the lining of your oesophagus, which can then be studied in the laboratory.  

At the end of the Cytosponge test, you complete a questionnaire. It asks about your feelings during the test.

Then, you have an endoscopy.    

During the endoscopy, as well as taking standard biopsies, the study doctor will take some extra tissue. This is to look for biomarkers to see why some people are more at risk of oesophageal cancer than others.

You also have some extra blood tests. Researchers want to see if people with squamous dysplasia have special markers (DNA) in their bloodstream.

Doctors will ask you to have a blood test each time you attend for follow up. You do not have to agree to have these tests done every time if you don’t want to. You can still take part in the study.

Depending on the results, you may have more endoscopies in the future. The study steam may also ask you to have the Cytosponge test again.  

People with oesophageal SCC
You have any tests, investigations and treatment as normal. As part of this study the researchers will ask you to have extra blood tests and biopsies.

The blood tests and biopsies are taken at set times. The study team can give you more information on how often you have them.

They will look for DNA in your blood and tissue samples to see if it is possible to get DNA from the cancer in the blood (this is called circulating tumour DNA).

Researchers will use the results of the tests to develop a new way of working out how advanced oesophageal cancer is (cancer stage). They think this will give doctors more information about the likely outcome (prognosis) of the cancer than the system used at the moment.  

Medical records
The team will ask you for permission to look at your medical records after you finish the study and for up to 10 years. They want to find out how you are and if your health changes over time.

Only people involved in this research will look at your records.

The study team will also ask you for contact details. They might contact you in the future to see how you are and to let you know about other clinical trials you might be interested in.

Hospital visits

You don’t have any extra visits as part of this study.

The Cytosponge, blood tests and any biopsies are done at the same time of your normal hospital visits. 

Side effects

Around 2000 people have had the Cytosponge test. It is not painful and the most common side effect is a mild sore throat for 1 to 2 days.   

You may also have some side effects from the endoscopy. 

We have more information about having an endoscopy.  



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 Rebecca Fitzgerald

Supported by

Cambridge University Hospitals NHS Foundation Trust
Cancer Research UK 
MRC Cancer Unit - University of Cambridge
NIHR Clinical Research Network: Cancer

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.

Cara took part in a clinical trial

A picture of Cara

"I am glad that taking part in a trial might help others on their own cancer journey.”

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