A trial to find the best timing for radiotherapy and chemotherapy for advanced non small cell lung cancer (SOCCAR)

Cancer type:

Lung cancer
Non small cell lung cancer




Phase 2

This trial looked at giving a course of radiotherapy and chemotherapy together, or one after the other, to see which might work best for non small cell lung cancer. This trial was supported by Cancer Research UK.

Non small cell lung cancer (NSCLC) that can’t be removed with surgery is often treated with chemotherapy and radiotherapy.

Some doctors thought that treatment may work better if patients had chemotherapy and radiotherapy at the same time (concurrently), rather than one after the other (sequentially). But this was a new way of treating NSCLC, and they were not sure how well it would work.

The aims of this trial were to collect information about the side effects of concurrent treatment and sequential treatment and to find out how well each treatment plan worked for non small cell lung cancer that could not be removed with surgery.

Summary of results

The trial team found that chemotherapy alongside 4 weeks of radiotherapy (concurrent treatment) is safe and can help people with non small cell lung cancer.

This trial was originally a phase 3 trial. But recruitment into the trial was slower than the researchers hoped. After talks with the steering committees, including the Independent Data Monitoring Committee (IDCM), it was decided to change SOCCAR to a phase 2 trial looking at the side effects of having concurrent treatment and how many people survived.

It was a randomised trial that recruited 130 people. They were put into 1 of 2 treatment groups. Neither they nor their doctor could choose which group they were in.

  • 70 people had chemotherapy alongside radiotherapy (concurrent treatment)
  • 60 people had chemotherapy then radiotherapy (sequential treatment)

The study started recruiting people in 2005, and they were followed up until January 2011. By the end of the trial, the number of people who were still alive was

  • 26 out of the 70 people (37%) who had concurrent treatment
  • 17 out of the 60 people (28%) who had sequential treatment

The overall average length of time people lived was

  • Just over 2 years for those who had concurrent treatment
  • About 1½ years for those who had sequential treatment

Overall there were fewer side effects and they were less severe in the concurrent treatment group than the sequential treatment group. The most common side effects reported in both groups were

  • A drop in blood cells causing an increased risk of infection, bruising and bleeding
  • Tiredness (fatigue)
  • A change to the way the lungs work
  • Feeling or being sick
  • Inflammation of the food pipe (oesophagus)
  • Numbness and tingling

The trial team concluded that having chemotherapy alongside 4 weeks of radiotherapy (concurrent treatment) could be safe and helpful for people who had non small cell lung cancer. They recommended that further research should be done to find out more about how helpful it could be.

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) and 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

Dr Joe Maguire

Supported by

Cancer Research UK
Experimental Cancer Medicine Centre (ECMC)
NIHR Clinical Research Network: Cancer

Other information

This is Cancer Research UK trial number CRUK/04/006.

Freephone 0808 800 4040

Last review date

CRUK internal database number:

Oracle 381

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

Cara took part in a clinical trial

A picture of Cara

"I am glad that taking part in a trial might help others on their own cancer journey.”

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