Every-other-year mammography screenings result in larger tumors, more aggressive treatment
University of Michigan researchers are casting doubts on the belief that it’s OK for women to be screened for breast cancer less frequently than once a year.
Currently, there are differing opinions on whether women over the age of 40 should receive mammography exams on a yearly basis or biennially. Wanting to quash this confusion for providers and patients, researchers from the school’s Rogel Cancer Center compared outcomes for dozens of diagnosed women.
Sarah Moorman, MD, and colleagues found that nearly half of those screened every other year had late-stage cancer, compared to just one-quarter of those on an annual schedule. Less frequent mammography screenings also led to more aggressive treatment down the line, according to their investigation, set to be shared Dec. 4 at the Radiological Society of North America’s 2019 annual meeting.
“Our study found that screening mammography performed once a year resulted in less advance stage disease in patients diagnosed with breast cancer,” Moorman, a radiology resident at Michigan Medicine, said in a school announcement. “These results may help women make informed decisions about the frequency of breast cancer screening,” she added.
The Michigan team came to their conclusions by comparing tumor characteristics and treatment regimens for 232 women between the ages of 40 and 84. They found that about 86% underwent annual screenings compared to about 14% who were assessed every two years.
Almost 44% of those in the biennial group had late-stage breast cancer compared to 24% of those seen more frequently. And more than one-third of women receiving mammography screenings every two years later got “interval cancer” between screenings, compared to 10.5% of their counterparts.
Less frequent appointments also forced clinicians to use more aggressive treatments down the line, including chemotherapy and removal of lymph nodes, where cancer can often spread. The authors hope these results put to rest the notion that anything less than an annual checkup is OK.
“Mammography is one of the few screening tools that has been proven to save lives,” co-author Mark Helvie, MD, a Michigan Medicine professor of radiology, said in the announcement. “This study confirms the benefit of more frequent annual screening.”