This is a
phase 2 trial. Researchers hope that around 46 people will agree to take part.
Everyone has the same treatment. You have pembrolizumab as a
drip into your vein every 3 weeks. It takes about 30 minutes each time you have it. You continue to have pembrolizumab for as long as the treatment is helping you and the side effects aren’t too bad. You can have treatment with pembrolizumab for up to 2 years.
You start radiotherapy after the 5th pembrolizumab treatment. This is usually about 3 months after the start of treatment. You have 3 radiotherapy treatments (fractions) in total.
If your cancer gets worse before the 5th pembrolizumab treatment, you start radiotherapy as soon as possible and you stop pembrolizumab treatment.
Blood tests
You have extra blood tests as part of this trial. Doctors want to look for certain proteins (biomarkers) that can help to tell how well the treatment is working.
You have the extra blood tests before the start of treatment.
Doctors might also ask you to have extra blood tests:
- after the 3rd and the 5th pembrolizumab treatment
- if your cancer gets worse or disappears
You don’t need to agree to have extra blood tests after the start of pembrolizumab if you don’t want to. You can still take part in this trial.
Tissue sample
Doctors ask to use a sample of cancer they took during a
biopsy 
or surgery (archival tumour sample). You need to give a new sample of tissue if there isn’t a suitable sample available that is less than 6 months old.
Doctors may also ask you to give new tissue samples:
- after the 3rd and the 5th pembrolizumab treatment
- if your cancer gets worse or disappears
You don’t need to agree to give extra tissue samples if you don’t want to. You can still take part in this trial.
Quality of life
- at set times during the trial
- when you finish treatment
The questionnaires ask about how you have been feeling and what side effect you have had.