THURSDAY, Jan. 22, 2004 (HealthDayNews) -- Popular perception to the contrary, cancer patients who participate in clinical trials may not actually have better treatment outcomes than those who don't take part in such trials, a new study says.
This is not to say patients are worse off, but experts don't really know one way or the other. "That's a question that can't be answered," says Dr. Joel Horovitz, director of general surgery at Maimonides Medical Center in New York City.
Somehow, though, the idea that patients in trials benefit has become part of the common lore.
"A lot of people in oncology have said that you're better off being in a clinical trial, either randomized or single arm, than being treated outside a clinical trial," says Dr. Steven Joffe, senior author of the study. Joffe is a pediatric oncologist at Dana-Farber Cancer Institute, Children's Hospital Boston, and Harvard Medical School, all in Boston.
The research appears in the Jan. 24 issue of The Lancet.
It's not entirely clear where that supposed benefit, commonly known as a "trial effect," come from. It could possibly be from new drugs (thought to be better than old ones), from being more closely monitored by medical professionals, or, perhaps, from doctors more carefully following standard treatment plans.
"People haven't really, for the most part, been clear about whether the supposed benefit comes from new treatments or just better administration of standard treatments," Joffe says. "It's all lumped together."
Even the fact of a benefit apparently has not been well documented.
Joffe and his colleagues reviewed 26 published studies that compared the health outcomes of cancer patients in trials with outcomes of those not in trials. While 14 of the studies did indeed suggest a better outcome, the authors conclude that most of the studies did not control well for bias.
Studies that showed positive outcomes were more likely to involve children and patients being treated earlier in their disease process.
"If there is a benefit from being in a clinical trial, then you would expect those within the clinical trial to do better, to survive longer," Joffe says. "We found some evidence to support that, but those studies are really hard to do because you have to make sure the two groups are the same."
If the group receiving the new treatment is five years younger or just a little bit healthier, then it's not a fair comparison and the results will be skewed. "You don't know if the differences reflect the treatment or the fact that they were different to start with," Joffe points out. "Maybe they're going to a better treatment center, so the message is not necessarily get yourself into a trial but go to a good treatment center."
But another message that Joffe wants to stress is that people should still sign up for clinical trials. "I want people to sign up, but I don't want them to sign up on the basis of a statement that I can't substantiate," he says. Rather, participants should think of themselves as part of a larger, valiant effort to improve medicine for future patients.
"I encourage patients and parents on the basis of this -- of how we can make things better [for everyone]," Joffe says.
This new altruistic bent may go against how many people currently make their decisions.
"I think the real reason patients enroll in a trial is that they feel their only shot is if they get access to some experimental drug that turns out to work," Horovitz says. "Most of my patients want to do it because they feel that's the only shot they're going to get for themselves, not that they're going to benefit mankind."