A trial comparing different ways of giving radiotherapy for prostate cancer (CHHIP)

The results so far show that hypofractionated treatment is as good as 37 fractions of radiotherapy, and doesn’t cause more side effects.

More about this trial
Everyone taking part in this trial had prostate cancer. They were all due to have radiotherapy as part of their treatment.

The research team compared 3 different doses of radiotherapy:

• Group 1 = 74 Gy in 37 fractions (standard treatment at the time) 
• Group 2 = 60 Gy in 20 fractions (hypofractionated treatment)
• Group 3 = 57 Gy in 19 fractions (hypofractionated treatment)

The 3,216 men who took part in this trial were put into 1 of these 3 groups at random. There were:

• 1,065 men in group 1 
• 1,074 men in group 2 
• 1,077 men in group 3

 

How well treatment works
In 2016 the team published some results about how well the treatment works. They looked at how many people didn’t have signs of cancer according to their PSA blood test or a clinical examination.

It was similar in all 3 groups:

• just under 9 out of 10 people (88%) in group 1
• just over 9 out of 10 people (91%) in group 2
• less than 9 out of 10 people (86%) in group 3

When they looked at how many people had died, this was also similar in the 3 groups. About 8 out of every 100 people (8%) had died, but only 1 person out of every 100 (1%) died because of prostate cancer.

Results published in 2018 showed that 57Gy in 19 fractions worked well for men over 75 years old. And didn’t cause too many side effects.

Side effects
In 2016 the researchers looked at how many people had moderate or severe bowel related side effects at some point in the 5 years during and after treatment. It was just over 1 in 10 (10%) for each group:

• 14 % for group 1
• 12% for group 2 
• 11% for group 3 

And the number of people who had moderate or severe bladder related side effects at some point in the 5 years during and after treatment was about 1 in 10 (10%):

• 9% for group 1
• 12% for group 2 
• 7% for group 3

Quality of life
2,100 people taking part agreed to complete questionnaires about how much the side effects were affecting their quality of life. In other words, how bothered they were by side effects they were having. The research team analysed the results in 2015. 

They found that about 6 out of 100 people (6%) were moderately or severely bothered by bowel problems 2 years after radiotherapy:

• 6 % for group 1
• 6% for group 2 
• 5% for group 3 

And that a similar number were moderately or severely bothered by bladder problems 2 years after radiotherapy:

• 5% for group 1
• 5% for group 2 
• 6% for group 3

Problems with sexual function were more common. Nearly 4 out of 10 (40%) men were moderately or severely bothered by problems with sexual function, 2 years after radiotherapy:

• 37% for group 1
• 39% for group 2 
• 38% for group 3

In 2019 and 2020, the researchers published more results that showed how using new radiotherapy techniques can reduce side effects even more. An example of this is image guided radiotherapy (IGRT), which helps reduce the dose of radiotherapy to the blood vessels at the base of the penis.

Conclusion
The research team concluded that giving fewer (but higher) doses of radiotherapy was as good as the standard treatment, and didn’t cause more side effects. 

They suggest that 60 Gy of radiotherapy in 20 fractions should be the new standard treatment. And that 57 Gy in 19 fractions could be an option for men over 75 years old.

Where this information comes from
We have based this summary on information from the research team. The information they sent us has been reviewed by independent specialists (peer review ]) 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.