“If you undergo mammography ever two years, you are not any more likely to end up with some advanced breast cancer than if you had annual screenings,” states Dr. Karla Kerkilowske of the University of California, San Francisco, School of Medicine, whose new study shows that some women 50 and older do not need to be tested as often as previously recommended.
Kerkilowske and her colleagues evaluated nearly 12,000 women (ages 50-74) with breast cancer, as well as an additional 922,000 without the disease, taking into consideration whether or not they had high density breast tissue as well as whether they were taking combination hormone therapy with estrogen and progestin (both considered high risk factors for breast cancer).
Although they did find that biennial mammograms were linked with nearly “twofold increased risk of advanced-stage cancers and large tumors for women 40-49 with dense breasts,” there were also a lot of false-positives reported during screenings.
The researchers also found that in general, false-positives for all mammograms among women ages 66 -74 went down in the group that had the tests every two years. For example, 48% of women who were screened annually had false positives while only 29% who were screened every other year had false positives.
Note: Current guidelines from the U.S. Preventative Services Task Force, updated in 2009, recommend that women aged 50 to 74 years only be screened every two years. It should also be cited that Kerkilowske’s findings, published online yesterday in the JAMA Internal Medicin,e have elicited mixed reactions, including criticism for its methods from other experts. Those interested in reading her report for themselves can view it at http://archinte.jamanetwork.com/onlineFirst.aspx