TUESDAY, Sept. 16, 2003 (HealthDayNews) -- The distance you need to travel for medical care probably isn't something you or your doctor think much about. But, the results of a new study suggest maybe you should.
In the Sept. 17 issue of the Journal of the National Cancer Institute, researchers report that people enrolled in a phase II clinical trial for treatment of head and neck cancers fared better if they lived more than 15 miles from the center where they were receiving treatment.
The next step is to determine why that's so. The link between distance traveled and response to treatments could also have implications for future clinical trials and drug approvals, researchers say.
"We found that patients who traveled a great distance for treatment have better outcomes than those who live close," says the study's lead author, Dr. Elizabeth Lamont, an assistant professor of medicine at Massachusetts General Hospital Cancer Center in Boston.
Lamont and her colleagues recruited 110 people with Stage IV squamous cell cancer of the head or neck for this study. All were involved in a phase II clinical trial of a chemotherapy and radiation combination to treat their cancer. According to Lamont, the therapy given was very aggressive with a lot of toxicity.
The researchers gathered information about each volunteer's age, sex, race, income, education, smoking and alcohol use history, other illnesses, as well as information on the distance each person had to travel. They then split the volunteers into two groups for evaluation: those who traveled less than 15 miles and those who traveled more than that for treatment.
The people who traveled more than 15 miles were more likely, on average, to be white, male, college educated, wealthier, and less likely to have a heavy alcohol use history.
The researchers found that those who traveled more than 15 miles for their cancer care had one-third the risk of death compared to people who lived nearby. These results held true even after the researchers accounted for data such as education and income.
"The challenge now is to find out what makes the people who travel a great distance do so well," notes Lamont, who was working at the University of Chicago at the time of the study.
Lamont says the researchers don't know what it is about people willing to travel for treatment that makes them do so well. Possible explanations include having a social network that helps them find the best treatment or helps them get to and from treatment. Also, she says, it could be that people willing to travel are more motivated. Or, it could be another unknown factor altogether.
The concern, however, is that distance traveled for treatment is a factor rarely accounted for in these types of clinical trials.
In an accompanying editorial in the journal, Stephen George, a professor of biostatistics from Duke University says, "If the studies they considered had been restricted to distant patients, the overall results would have been impressively positive. Conversely, had they been restricted to local patients, the results would have been discouragingly negative."
Phase II clinical trials are used to evaluate how effective a medication is and to further investigate its safety. They usually involve several hundred patients. In phase II trials, drugs are not compared to other drugs or a placebo. If a treatment does well in phase II trials, it will usually move on to phase III trials, which involve many more patients.
Normally, says George, that's not a problem, because phase II trials typically progress to phase III trials, where patient treatment is randomized, so the distance traveled wouldn't be a factor. But, in the mid-1990s, the U.S. Food and Drug Administration introduced the accelerated approval process and some drugs now receive initial approval based on the results of phase II trials.
"Results of phase II trials can be highly dependent on the kind of patients enrolled," says George. "This study shows that a variable that is almost never reported -- how far patients live -- seems to be a very important variable. This study carries a warning for relying on these kinds of trials for regulatory decisions."