Jan. 5, 2009
UI neurosurgeon leads efforts to advance evidence-based cancer care
Evidence-based medicine -- using the best evidence gained from scientific studies to inform medical decision-making -- currently is a hot topic in health care. And, according to a University of Iowa neurosurgeon, it is important in helping physicians and patients make the best treatment choices and can also be a useful tool for controlling health care costs.
"An evidence-based approach tries to provide a systematic appraisal of the available data -- it levels the playing field of ideas," said Timothy Ryken, M.D., associate professor of neurosurgery at the UI Roy J. and Lucille A. Carver College of Medicine. "Each study is subjected to the same set of tests to determine the quality, rigor and significance of the findings, which is beneficial because, at least in theory, it removes subjective judgments."
Repetition of views and opinions, particularly in authoritative places like textbooks, can lead to ideas becoming entrenched dogma. Moreover, reviewing the original data can sometimes reveal that the evidence to back up these ideas is not always robust.
"Sometimes, we don't know as much about things as we think we do," Ryken said. "It's important to critically review the original data to determine what is the best information out there on which we should base our decision-making process."
Specialists in neurosurgery have led the way in developing evidence-based practice guidelines, including guidelines for severe head injury and spinal cord injury.
Ryken, who also has a master's degree in epidemiology from the UI College of Public Health, has a particular expertise in developing and reviewing evidence-based guidelines. He currently is co-chairman of the American Association of Neurological Surgeons and Congress of Neurological Surgeons Joint Guidelines Committee, where he helps lead a group of around 25 physicians who review guidelines related to neurosurgery ensuring they meet certain standards in regard to methodology.
Ryken is quick to stress that evidence-based guidelines provide a framework for decision-making rather than rules for which treatment options should be used.
"Physicians generally don't like to be told what to do. But these guidelines are really a way of protecting options when there are multiple ways of doing things, rather than dictating what should be done," he said. "The guidelines also are a work in progress and need to be constantly updated as new studies become available."
Recently, Ryken led a group of physicians that published a series of guidelines for the treatment of newly diagnosed glioblastoma.
Glioblastoma is the most aggressive and most common type of primary brain tumor. There currently is no cure, and median survival is around one year. In fact, gains in survival have been very small over the past 25 years. There are between 200 and 300 new cases in Iowa each year, and many of those patients are treated at Holden Comprehensive Cancer Center at the UI.
Ryken and colleagues, including John Buatti, M.D., UI professor and head of radiation oncology and deputy director of clinical cancer care for Holden Center, and Mark Smith, M.D., UI assistant professor of radiation oncology, formed five committees to review and assess the literature published between 1966 and 2007 in the areas of neuro-radiology, neurosurgery, neuropathology, radiation oncology and neuro-oncology. Each committee produced a report of their findings and the combined guidelines were published in the September 2008 issue of the Journal of Neuro-Oncology.
The guidelines primarily summarize the currently available knowledge related to the management of newly diagnosed glioblastoma and serve as a point of departure for further research.
A secondary goal of the guidelines was to provide a scientific basis for current medical practice in the management of newly diagnosed glioblastoma. In this respect, the reports provide strong support for the use of radiation therapy as a first line treatment for glioblastoma. The evidence also bolsters the use of surgery to remove as much of the tumor as possible while minimizing loss of health brain tissue. However, evidence supporting brachytherapy and stereotactic radiosurgery was not as strong, suggesting that these therapies should not be used as an initial treatment.
"What we have tried to do is provide a comprehensive look at the state-of-the-art of management of these malignant tumors to provide treating physicians as well as patients with a baseline of the current therapies," Ryken said. "The guidelines should provide a platform on which to build and hopefully lead to a more substantial improvement in survival for these patients."
In addition to informing medical practice, evidence-based medicine also is useful for health care economics. For example, when the evidence shows that two different treatments produce equivalent outcomes but one treatment costs more than the other, then use of the more expensive treatment should require additional justification.
Evidence-based medicine also plays a role in outcomes research, or how patients do over the long term.
"Being able to show that we can take better care of a patient with one method over another helps physicians and patients make more informed decisions about their care and thus improve outcomes," Ryken said. "On the other hand, sometimes there may not be a great difference in outcomes, which means a patients can choose treatments based on other criteria."
STORY SOURCE: University of Iowa Health Science Relations, 5135 Westlawn, Iowa City, Iowa 52242-1178
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