TUESDAY, July 19, 2005 (HealthDay News) -- A real-world look at the benefits of breast cancer screenings has turned up some dismaying news: Screening rates for women who died from the disease were no different from the screening rates of those who were cancer-free.
The U.S. researchers who conducted the study, however, hastened to add that women should not stop getting routine mammograms and clinical breast exams based on these findings.
"Women should continue current screening as recommended," said lead researcher Dr. Joann G. Elmore, a professor of medicine at the University of Washington School of Medicine in Seattle.
The study appears in the July 20 issue of the Journal of the National Cancer Institute.
"We did a case-control study," Elmore explained. "As the cases, we evaluated women who died of breast cancer, and as the controls, women who were matched for age and [similar] risk factors."
The researchers wanted to examine the theory that, if screening for breast cancer really works to prevent women from dying of the disease, women still living should have had more screenings than women who died .
In all, Elmore's team looked at screening data on 1,351 women who died from breast cancer between 1983 and 1998, and compared it to data on 2,501 breast cancer-free women. All of the women received their regular care through six health plans in California, Massachusetts, Minnesota, Oregon and Washington.
They found that 69.8 percent of women aged 50 to 65 with an average risk for breast cancer who died from the disease had gotten mammograms, breast exams or both within the previous three years. For cancer-free women of similar age and risk, the percentage was almost identical: 69.2
Elmore's team did find a 26 percent reduction in breast cancer mortality associated with screenings in a subgroup of women at above-average risk for the disease due to family history or prior suspicious biopsy results. However, the number was not high enough to be statistically significant, the researchers noted.
The Seattle researcher was quick to emphasize that this does not mean women should stop getting mammograms. The findings are understandable, she said, when you consider that current recommendations for mammograms are based on data that was produced in the carefully controlled trials.
This new data comes from real-world situations, and Elmore believes one reason the results fall short of ideal is that the quality of community screenings is lower than those typically used in clinical trials.
Another factor, Elmore said, may be that new treatments have improved survival rates after breast cancer is detected, regardless of how it was detected or how often a woman went for screening.
Dr. Russell Harris, a professor of medicine at the University of North Carolina at Chapel Hill, who wrote the accompanying editorial, noted, "What women should understand is that this study is researchers talking to researchers. It is not a matter of saying 'Women should stop getting screened.'"
The issue to be discussed, he added, is whether there are ways to make breast cancer screening even better.
"It may well be that in some places screening doesn't find all the cancer it should find, or it could be that some women are not being screened as they need to be," he said.
"Screening is only part of the story," he said. "Screening is the first step. All these other steps [such as a biopsy, if necessary] have to work."
Elmore agreed. Women should continue going for their annual mammogram or clinical breast exam, "but they should realize that screening is not perfect or foolproof. They need to pay attention to their bodies. There are false negatives."
To improve the effectiveness of screening, "go to the same mammogram facility each year," Elmore advised. "They may have old films available for comparison. If you are having a period, ideally, go after your period, when the breast puffiness is gone."
Don't forget to get a clinical breast exam, too, she said. "A high quality screening breast exam [by a health care provider] should take no more than seconds."
More information
To learn more about breast cancer, visit the
American Cancer Society.
