June 23, 2010
OAK BROOK, Ill. — The July issue of Radiology contains two editorials offering opposing viewpoints on the recent United States Preventive Services Task Force (USPSTF) recommendations for breast cancer screening.
One editorial was written by members of the USPSTF and provides an overview of the task force, the process and the evidence behind the recommendations.
The second editorial, by Daniel B. Kopans, M.D., professor of radiology at Harvard Medical School and senior radiologist, Breast Imaging Division, at Massachusetts General Hospital in Boston, challenges the new screening mammography guidelines and asserts that the task force ignored important scientific evidence when making its recommendations.
"We greatly appreciate the invitation from the editors of Radiology to provide an account of our methods and the opportunity to clarify aspects of the recommendations that have been misinterpreted by some," said Ned Calonge, M.D., M.P.H., USPSTF chair and chief medical officer of the Colorado Department of Public Health and Environment.
"Radiology should be complimented for allowing both sides of this debate to be provided equally by experts on the topic," Dr. Kopans said.
The USPSTF has a rotating membership of 16 experts in a variety of medical specialties. The USPSTF evaluates the benefits of individual services on the basis of age, gender, and risk factors for disease and makes recommendations about which preventive services should be incorporated routinely into primary medical care for specific population groups.
"USPSTF recommendations are made to help guide primary care physicians and nurses in providing effectively preventive services," Dr. Calonge said. "Recommendations are made solely on the basis of rigorous, impartial analysis of the best scientific evidence."
The breast cancer screening guidelines issued by the USPSTF in November 2009 sparked a controversy among physicians, patient advocacy groups and the media. While a few of the recommendations were questioned—including the recommendation against clinician-taught breast self-exam and the recommendation for screening for women between the ages of 50 and 74 every two years instead of annually—much of the debate centered on the recommendation against routine annual mammography screening for women in their 40s.
The USPSTF editorial states that some of the controversy stems from a misinterpretation of a wording change in the Grade C recommendation category, which formerly read "does not recommend for or against" and was amended to "recommends against routine provision," as a response to input from primary care physicians.
"The USPSTF recommends that women between the ages of 40 and 49 discuss the potential benefits and harms of mammography with their primary care physicians and nurses to help them make informed, individual decisions about when to begin regular breast cancer screening mammography," Dr. Calonge said.
"Medical evidence indicates that many women in their 40s who get routine screening mammograms will undergo unnecessary tests, procedures and, very rarely, treatment without any health benefit, while other women—about one per thousand—will have their lives extended by mammography," he added.
Dr. Kopans disagrees.
"The death rate from breast cancer had been unchanged for 50 years until the onset of mammography screening in the U.S. in the mid-1980s," he said. "Now, there are 15,000 to 20,000 fewer deaths from breast cancer each year than in the pre-screening era. The USPSTF guidelines would reverse this major advance."
In his account, Dr. Kopans questioned the methods of the USPSTF and the evidence considered in making its mammography recommendations. He contended that the task force used age 50 as a threshold for women to begin breast cancer screening when there are no data to support age 50 as a threshold. In addition, he wrote that the analysis underestimated the reduction in mortality, citing 15 percent when the data suggest that breast cancer screening decreases the number of deaths by 30 percent or more.
Dr. Kopans criticized the USPSTF's use of computer modeling instead of favorable, direct population-based screening results from the Netherlands and Sweden. He also took issue with specific USPSTF recommendations.
"They advised against routine screening for women in their 40s unless a woman is at high risk," Dr. Kopans said, "but the vast majority of women who develop breast cancer each year are not at high risk."
He also questioned the recommendation in favor of screening women between 50 and 74 every two years instead of annually.
"Therapy only saves lives if cancers are found early," Dr. Kopans said. "The USPSTF guidelines are not based on scientific evidence. Women should be urged to begin annual breast cancer screening at the age of 40."Related podcast: