A study using breath to predict what happens to tissue during radiotherapy for prostate cancer (PRINToUT)

Cancer type:

Prostate cancer





This study is looking at pieces of DNA Open a glossary item in the blood and urine (ctDNA Open a glossary item) and scans. This is to see if they can predict what happens to cancer and normal tissue. Also to predict how well radiotherapy works. 

It is open to men with early prostate cancer Open a glossary item who are going to the Western General Hospital, Edinburgh. 

More about this trial

Radiotherapy is one of the treatments doctors can use for early prostate cancer

Researchers are looking at using:

  • ctDNA in the blood
  • the time of treatment scans

They want to try and predict:

  • how well radiotherapy might work
  • how radiotherapy might affect the surrounding healthy tissue

In this study you have stereotactic body radiotherapy Open a glossary item (SBRT or SRT). You have 5 treatments. Before and after each treatment the team take a sample of your breath. During the study they also take:

  • a sample of spit (saliva)
  • urine samples
  • blood samples 

They use these samples to look at your normal tissue DNA Open a glossary item and any free tumour circulating DNA (ctDNA Open a glossary item) from the prostate cancer. 

The aims of the study are to:

  • find substances (biomarkers Open a glossary item)  that could predict how well radiotherapy works
  • see whether circulating normal tissue and tumour cell free DNA can predict how well the radiotherapy is working
  • see whether analysis of the time of treatment scans can predict how the radiotherapy is working

Who can enter

The following bullet points are a summary of 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. 

Who can take part

You may be able to join this study if you are going to the Western General Hospital, Edinburgh and all of the following apply. You:

  • have prostate cancer stage 1 or stage 2
  • have a Gleason score Open a glossary item of 3+3=6 or 3+4=7. Your doctor will know this.
  • have a PSA Open a glossary item of 20ng/ml or less. Your doctor will know this. 
  • have a prostate volume of 90cc (cubic centimetres) or less. Your doctor will know the volume of your prostate.
  • have an International Prostate Symptom Score (IPSS) of 20 or less. Your doctor will ask you some questions to work out what your IPSS is.
  • have a certain flow rate of urine and the amount of urine left in the bladder after urinating is less than 250mls. Your doctor will be able to work these out.
  • can have radiotherapy with the aim to cure your prostate cancer
  • are able to look after yourself but might not be able to work (performance status 0, 1 or 2)
  • are between 18 and 80 years old

Who can’t take part

You cannot join this study if any of these apply. You:

  • have had a transurethral resection Open a glossary item of the prostate (TURP)
  • have a Gleason score of 4+3=7, 8, 9 or 10 
  • have had hormone treatment for more than 6 months or previous surgery to remove your testicles (orchidectomy)
  • have had radiotherapy to the pelvis Open a glossary item before
  • have a medical condition such as inflammatory bowel disease that means you might not be able to have radiotherapy
  • have any other medical condition or mental health problem that could affect you taking part 

Trial design

The team hope to recruit up to 48 men to take part. 

Before your radiotherapy you have a planning appointment. This is to work out the dose of radiotherapy to give and where to give it. You also have gold fiducial markers put in place. This is to make sure you have the radiotherapy in the correct place. You have antibiotics after to prevent possible infection. 

You have 5 treatments with stereotactic body radiotherapy. This usually starts on a Wednesday and finishes the next Tuesday. You don’t have treatment on the Saturday or Sunday. The machine used to give the radiotherapy is a Linear Accelerator (LINAC). 

You have a special type of urinary catheter called a HypoCath put into your bladder on the day before you start radiotherapy. This remains in during the whole 5 days of treatment.

During treatment the catheter is attached to the LINAC. This helps the LINAC track the movement of the prostate. So that the radiotherapy targets the prostate cancer the whole time. 

Each radiotherapy treatment takes between 30 and 40 minutes. 

The catheter should stay in during the whole 5 days. If it doesn’t the team can replace it.

Research samples and tests
You give a spit (saliva) sample once. The research nurse or the radiographer collects this and will tell you how to do it. They can take this sample on any of one of the 5 days. 

The team also take blood samples and urine samples before each treatment. And then 1 and 3 hours after treatment.

Quality of life
You fill in questionnaires:

  • before starting radiotherapy
  • after your last treatment
  • then for up to 2 years after 

The questions ask about:

  • your general health and wellbeing
  • what you are able to do 
  • side effects and symptoms

These are quality of life questionnaires

Hospital visits

There are no extra hospital visits if you take part. But you will need to stay for up to 3 hours after each radiotherapy treatment for the team to collect the breath samples, blood samples and urine samples. 

After treatment you see the doctor as part of the study at:

  • 6 weeks
  • 3 months
  • 6 months
  • 12 months
  • 18 months 
  • 24 months

At these times you give a: 

  • blood sample
  • urine sample 

Side effects

The team don’t anticipate any side effects or problems during the study. 

We have information about having radiotherapy to the prostate.



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 Duncan McLaren

Supported by

University of Edinburgh
NHS Lothian
Jamie-King Urological Cancers Research Fund

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.

Last reviewed:

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