Women over age 75 do not experience a clear benefit if they continue receiving screening mammograms, new research has determined.
Investigators from the Harvard T.H. Chan School of Public Health, Massachusetts General Hospital, and RTI Health Solutions, revealed results in the Annals of Internal Medicine this week that showed that, even though there is no clear age at which women should stop getting mammograms, there’s no additional survival benefit after age 75. Currently more than 50 percent of women over age 75 get mammograms.
“Among women who have had at least one screening mammography, our estimates suggest that continuing screening past age 75 years results in no material difference in cancer-specific mortality over the following 8-year period compared with screening cessation,” wrote the authors, led by Xabier García-Albéniz, M.D., Ph.D, from the Harvard epidemiology department.
Investigators analyzed data from more than 1 million women ages 70 to 84 who had traditional Medicare Parts A and B coverage between 2000 and 2008. The women had a life expectancy of more than 10 years, a history of previous mammograms, but no breast cancer history. They divided the group into two subsets – those who continued annual mammograms and those who stopped. The women were also categorized by age: 70 to 74 and 75 to 84. The team followed the women for 16 months, on average, until the participant died, was no longer enrolled in fee-for-service Medicare, or until December 2008.
According to the study results, 1,533 women who continued screening and 1,304 women who didn’t died during the follow-up period. Among those who continued screening, the breast cancer risk was 5.5 percent, and it was 3.9 percent for those women who ceased getting mammograms. When broken down by age, in the screening cohort, the 70-to-74 age group had a 5.3 percent risk, and the 75-84 group had 5.8 percent risk. The risk for the non-screening cohort was 3.9 percent for both age groups.
The study also provided insight into the positive predictive value for post-baseline mammography visit. For women who continued screening, it was 38.5 percent. For those who didn’t, it was 45.3 percent. Results showed positive predictive values for the younger group as 35.8 percent and 42.2 percent, respectively, as well as 41.5 percent and 48.4 percent for the older group.
Ultimately, because there’s a lack of knowledge and research into the impact of screening mammography in women over age 75, Otis Brawley, M.D., a cancer screening thought leader from Johns Hopkins University departments of oncology and epidemiology, noted, in an accompanying editorial, there is a need for continued work on this topic.
“Hopefully, breast cancer treatment of the geriatric population will improve, and future studies can show that quality screening and treatment lead to a reduction in ‘overall mortality’ instead of just ‘breast cancer-specific mortality.’”