Trials 'do not benefit patients'

Most studies of trials are flawed, say researchers in the US

There is little proof that taking part in clinical trials alone is enough to improve outcomes for cancer patients, research has found.

Many people believe participation can help, regardless of the treatment.

But researchers at Boston's Dana-Farber Cancer Institute found "insufficient data" trial patients fared better.

Writing in the Lancet, they said it should be stressed to patients that the trial was designed not to help them, but others in the future.

Sometimes trials will benefit individuals, but we can't promise it and I don't think we do Kate Law, Cancer Research UK

New drugs and treatments given to patients during clinical trials often do prove to be more effective than standard treatments.

It has been thought that some patients benefit from other factors, such as more focused care and the potential psychological boosts from taking part in a trial.

However, the Dana-Farber researchers say there is little evidence that this is the case.

They say evidence of better outcomes is sketchy, and may be influenced by factors such as people who volunteer for trials being more upbeat or from a particular age or social group.

It could also be that improvements are shown up by closer monitoring than usual.

'Pervasive belief'

Researchers reviewed 26 studies, 14 of which suggested some patients benefited from taking part in trials.

But they said most were unreliable because they were badly designed - for example, only nine had the same criteria for recruiting patients into the trial and non-trial groups.

Of these, only three found that trial participants had better outcomes than non-participants.

Writing in The Lancet, the researchers said: "In our review of the published work, we found little high-quality evidence to support the pervasive belief that cancer trial participation leads to improved outcomes.

"Showing a causal relation between trial participation and improved outcome is difficult."

Dr Steven Joffe, who led the study, said: "Until more convincing evidence for a trial effect is available, recruitment messages to patients considering trials should focus on their contribution to advances in treatment."

'Good of mankind'

Kate Law, head of clinical trials for Cancer Research UK, told BBC News Online: "Sometimes trials will benefit individuals, but we can't promise it and I don't think we do.

"When patients are giving informed consent, they are never told that they themselves might benefit.

"Rather, they are told that it is an altruistic decision 'for the good of mankind'.

"It would be quite misleading to tell them otherwise, and I don't think it happens."

She said there was evidence patients benefited from better monitoring in trials - and that was why new treatment guidelines were being introduced for all cancer patients.

Less than 5% of adults with cancer are enrolled into clinical trials.