A trial looking at 2 different ways of giving radiotherapy for prostate cancer (PIVOTAL)

Cancer type:

Prostate cancer

Status:

Results

Phase:

Phase 2

This trial looked at radiotherapy for prostate cancer that had grown outside the prostate but had not spread to lymph nodes or another part of the body. It was supported by Cancer Research UK.

More about this trial

Doctors often treat prostate cancer with hormone therapy, surgery or radiotherapy to the prostate.

The men taking part in this trial had prostate cancer that was at risk of spreading to the lymph glands in the pelvis. The pelvis is the area surrounded by your hip bones. When this trial was done, the standard treatment for men in this situation was radiotherapy to the prostate, but not the pelvic area.

Everyone taking part in this trial had intensity modulated radiotherapy (IMRT). Some men had radiotherapy to the prostate only. And some had radiotherapy to the prostate and pelvic area.

The research team wanted to find out more about the side effects of these two types of radiotherapy.

This trial was done to see how well people cope with high doses of radiotherapy to the prostate and the lymph glands in the pelvis.

Summary of results

This trial showed that pelvic radiotherapy for prostate cancer didn’t cause too many serious side effects.

The research team recruited people between 2011 and 2013, and published the results in 2018.

Results

This trial recruited more than 120 men with prostate cancer that had grown outside the prostate, and doctors felt may spread to their pelvic lymph nodes.

The men taking part were put into 1 of 2 groups at random, and:

half had radiotherapy to their prostate only
half had radiotherapy to their prostate and pelvis

The research team looked at the side effects people had during and after treatment. They looked how many people in each group had side effects that affected their bladder or bowel. These include problems such as:

diarrhoea
inflammation or bleeding from the back passage (rectum)
inflammation of the bladder
needing to pass urine more often than usual

Bowel side effects

Some men had side effects that were mild or short lived. But a few had more serious side effects.

The biggest difference between the 2 groups was 6 weeks after starting radiotherapy, when the number of men having more serious side effects was:

4 out of 61 people (7%) who had radiotherapy to the prostate
16 out of 61 people (26%) who had radiotherapy to the prostate and pelvis

Over time the number of people with bowel side effects, and difference between the two groups, got smaller. The number of men having more serious side effects was similar in both groups by about 4 months (18 weeks):

2 people (3%) who had radiotherapy to the prostate
3 people (5%) who had radiotherapy to the prostate and pelvis

Bladder side effects

The number of men with bladder side effects was very low and similar in both groups. The side effects were worst about 8 weeks after starting treatment.

How well treatment worked

The main aim of this trial was to look at side effects, but the research team also looked at how well the treatments worked in the first 2 years.

They found that the cancer had grown or spread to another part of the body in a small number of men in each group. But it’s hard to draw any firm conclusions from a phase 2 trial because of the relatively small number of people taking part.

The trial team are looking at how well radiotherapy works in more detail in a larger phase 3 trial. We have more information about the PIVOTALboost trial on our database.

Quality of life

The people taking part completed several questionnaires to see how the treatment affected their quality of life. Researchers call these ‘patient reported outcomes’. They included questions about possible bowel and bladder problems.

The research team found that the answers were similar for the two groups. People in both groups reported more bowel problems 10 weeks after joining the trial. They had fewer problems as time went on.

Conclusion

The trial team concluded that radiotherapy to the prostate and pelvis was safe and didn’t cause too many serious side effects. It may be a useful treatment for prostate cancer, but researchers need to find out more about how well it works.

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.