A trial looking at treatment after surgery for kidney cancer (HYDRA)

Cancer type:

Kidney cancer
Renal cell cancer




Phase 3

This trial looked at using the drugs fluorouracil, interleukin 2 and interferon alpha after surgery to see if they could help improve the treatment outcome for kidney cancer. This trial was supported by Cancer Research UK.

Doctors treat renal cell cancer (kidney cancer) with surgery if possible. It often works very well, but sometimes the cancer starts to grow again or spreads to another part of the body.

Doctors thought that giving some people treatment after surgery may help stop the cancer coming back. But they were not sure how well this would work. All treatments have some side effects, so it is important that people don’t have treatments they don’t need.

In this trial, one group of people had the biological therapies interleukin 2 (IL-2, or aldesleukin) and interferon alpha (IFN), and the chemotherapy drug fluorouracil (5FU). The other group didn’t have any treatment after surgery, but had the usual care and follow up.

The aim of the trial was to find out if having the trial treatment after surgery helped stop renal cell cancer coming back.

Summary of results

The trial team found that having this treatment after surgery did not help stop renal cell cancer coming back.

This trial recruited 309 people. After surgery to remove their renal cell cancer, they were put into 1 of 2 groups. There were 154 people in group 1 and 155 people in group 2. People in group 1 had treatment with one of the following drugs

  • Interleukin 2
  • Interferon alpha
  • 5FU

People in group 2 had no extra treatment, but had the usual care and follow up after surgery.

Everyone taking part in this trial filled in a questionnaire asking them how they felt and what side effects they had. This is called a quality of life study. After 6 months of follow up there was no difference in the quality of life between the 2 groups.

In group 1, 35 out of every 100 people (35%) didn’t finish their treatment because of side effects.

People were followed up for an average time of just under 6 years.

After 3 years follow up the number of people whose cancer had come back was

  • 50 out of every 100 people (50%) in group 1
  • 61 out of every 100 people (61%) in group 2

After 5 years follow up the number of people alive were

  • 70 out of every 100 people (70%) in group 1
  • 63 out of every 100 people (63%) in group 2

The researchers concluded that the difference between the 2 groups could have happened by chance (the results were not statistically significant Open a glossary item). So there was no benefit from having the trial treatment for renal cell cancer after surgery. And that there were significant side effects from the treatment.

We have based this summary on information from the team who ran the trial. The information they sent us has been reviewed by independent specialists (peer reviewed Open a glossary item) but may not have been published in a medical journal. The figures we quote above were provided by the trial team. We have not analysed the data ourselves.

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

Mr Michael Aitchinson

Supported by

Cancer Research UK
European Organisation for Research and Treatment of Cancer (EORTC)
Experimental Cancer Medicine Centre (ECMC)
NIHR Clinical Research Network: Cancer

Other information

This is Cancer Research UK trial number CRUK/98/004.

If you have questions about the trial please contact our cancer information nurses

Freephone 0808 800 4040

Last review date

CRUK internal database number:

Oracle 62

Please note - unless we state otherwise in the summary, you need to talk to your doctor about joining a trial.

Wendy took part in a new trial studying the possible side effect of hearing loss

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"I was delighted to take part in a clinical trial as it has the potential to really help others in the future.”

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