Undergoing a mammogram every two years has the same benefit as annual mammograms for women over the age of 65, with the added advantage that it leads to fewer false positives, according to a study published online in the Journal of the National Cancer Institute.
In the study, researchers looked at data collected from 1999 to 2006 on 2,993 older women with breast cancer and 137,949 without. They found no difference in rates of late-stage breast cancer in those women screened annually compared to those screened every two years. They did find that 48 percent of women between the ages of 66 and 74 who were screened annually had false positive results, compared to just 29 percent of those screened every two years.
"Women aged 66 to 74 years who choose to undergo screening mammography should be screened every two years," senior author Karla Kerlikowske, M.D., a physician at the UCSF-affiliated San Francisco VA Medical Center, said in an announcement. "They get no added benefit from annual screening, and face almost twice the false positives and biopsy recommendations, which may cause anxiety and inconvenience."
Len Lichtenfeld, M.D., deputy chief medical officer for the American Cancer Society who was not involved in the study, told HealthDay News that the results of the study were not surprising.
"We've known that breast cancers in older women tends to be slower growing," he said.
Judith Malmgren, an affiliate assistant professor of epidemiology at the University of Washington told HealthDay that the study confirms earlier findings about biennial screening, adding that women with a family history of breast cancer should consider getting annual mammograms.