Large Portion of Late-Stage Breast Cancers Associated With Absence of Screening
Study results indicated that not having had a screening mammogram for 1 to 3 years prior to diagnosis was associated with 52 percent of late-stage breast cancer cases. The authors state that to improve breast cancer outcomes, priority should be placed on reaching unscreened women and encouraging them to have mammograms - especially older, unmarried, less educated, and/or low income women, whom they found were less likely to have been screened. "The good news is that there is a lot known about how to reach women who have never been screened or who fail to get regular mammograms," said Dr. Stephen Taplin, a senior scientist in NCI's Division of Cancer Control and Population Sciences and lead author of the study. "The challenge is to put this knowledge into practice."
The study was based on a review of all medical care received by 2,694 women during the 3 years prior to their breast cancer diagnosis. Researchers reviewed medical charts and records of women in seven integrated healthcare plans across the United States. The plans offer specialty and primary care within the same system, and serve 1.5 million women over age 50. All offer breast cancer screening mammograms at no or low cost. When the study began in 1999, 71 to 81 percent of these women had gotten mammograms. "Few women in a regularly-screened population should be diagnosed with late-stage breast cancer because, in theory, screening should identify cancers before they progress to the late stage," explained Taplin. "However, there were still cases of late-stage breast cancer in this population."
Women who had not been screened 1 to 3 years prior to diagnosis were more than twice as likely to have late-stage breast cancer. This illustrates an important reason for receiving regular mammograms: to increase the chance of catching breast cancer early. However, a second finding showed that better screening tests need to be developed. Almost 40 percent of women with late-stage breast cancer had a negative mammogram 1 to 3 years before their diagnosis.
In response to this study, NCI Director Dr. Andrew C. von Eschenbach stated, "This study helps us identify research priorities for breast cancer screening. To eliminate the suffering and death due to cancer, we need to improve delivery to reach women who don't receive regular mammograms, improve the interpretation of mammography, and find new screening tests. All these things are important to achieve national goals."