Patients who traveled at least 15 miles for care had one-third the risk of dying during the trial and follow-up period as those living closer. For every 10 miles that a patient traveled for care, the risk of death decreased by 3.2 percent. A similar pattern was seen with progression-free survival.
"This does not mean that time on the highway is curative," insists Everett Vokes, M.D., professor of medicine and chief of hematology/oncology at the University of Chicago and senior author of the study. "It does suggest that distance is a good marker for some unmeasured resource such as access to health care options, personality traits like compliance or motivation, or a supportive social network, that we don't yet know how to assess."
The results confirm something oncologists "have long appreciated," note the authors. Patients who explore therapeutic options and expend the resources to receive those therapies seem to "fare better than those who end up at the closest place," even if their diseases and treatments are the same.
The study, conducted by Vokes, a specialist in head and neck cancers, Elizabeth Lamont, M.D., (formerly at Chicago and now at the Massachusetts General Hospital Cancer Center in Boston) and colleagues, involved 110 patients with advanced (stage-IV) head and neck cancer who were enrolled in one of four phase II clinical trials at the University of Chicago Hospitals from 1993 to 2000.
All four trials involved aggressive treatment intended to eradicate the cancer. Patients received five cycles of combined chemotherapy plus twice-daily radiotherapy. Despite advanced disease, more than 60 percent of the patients enrolled in these trials go on to survive at least five years.
Although patients from near and far were comparable in terms of disease severity, those who traveled 15 miles or more tended, on average, to have higher incomes and more education and were more likely to be white. Patients who within 15 miles of the hospital were more likely to have had laryngeal cancer, which has a relatively favorable prognosis, and to be African American, also an advantage.
Unlike many previous studies, African Americans did better in these trials. "When treatment was standardized and health factors, social resources, and neighborhood effects were rigorously accounted for," the authors remarked, African Americans had "better survival outcomes than white patients."
Phase II trials, in which everyone gets the investigational treatment, are customarily used to determine whether a drug is promising enough to proceed to phase III trials, which compare the experimental treatment with the best standard therapy. The U.S. Food and Drug Administration has historically relied on results from phase III trials to determine whether or not to approve a drug.
Since 1995, however, the FDA has begun to approve some drugs based on results from phase II trials. In an accompanying editorial, Stephen George, Ph.D., of Duke University Medical Center, uses the results from this study to question that practice.
"Accelerated approval may provide earlier access to potentially beneficial agents," George writes, "but the evidence required for granting it should not come solely from phase II trials."
"If the studies they considered had been restricted to distant patients, the overall results would have been impressively positive," he notes. "Conversely, had they been restricted to local patients, the results would have been discouragingly negative."
Funding for the study came from the National Cancer Institute and the Francis Lederer Foundation. Additional authors include Davinder Hayreh, Kate Pickett, James Dignam, Marcy List, Kerstin Stenson, Daniel Haraf, Bruce Brockstein and Sarah Sellergren.
Journal
JNCI Journal of the National Cancer Institute