Nearly a third of post-breast cancer women are slipping through the cracks in our mammography system, according to a presentation at the 2016 Annual Clinical Congress of the American College of Surgeons.

Women who’ve been treated for breast cancer should get annual exams due to their risk of recurrence, according to the American Cancer Society. Previous studies suggest that not nearly enough women are following through, but the rates of underutilization are unknown.

“Most of what we know about breast imaging comes from small studies or from Medicare data, a population that is 65 years and older,” said Caprice C. Greenberg, MD, MPH, a professor of surgery at the University of Wisconsin-Madison School of Medicine and Public Health.

“This study is the first to look at a large, multi-institutional population of patients across all age groups,” she said.

UW researchers used a random sample of nearly 10,000 women who received surgery for breast cancer from 2006 to 2007, following them for five years. They were looking for three things; Imaging, recurrence, or death.

Researchers found that annual surveillance declined from 68 percent in the first year to 58 percent by the fourth year. Factors that decreased a woman’s participation in screening were young age, black race, public/no insurance, and poorer overall health.

 "The most striking finding is that over 30 percent of women don't even get surveillance breast imaging in the first place," Greenberg said. "For some reason, we are not plugging them into follow-up surveillance from the outset. We also see that there are some disparities in the use of mammograms after the treatment of breast cancer."

They also found only five to 10 percent of women who did get screened used MRI, which can be attributed to where they underwent screening.

According to Greenberg, the use of MRI often depends on local practice patterns as it’s not currently recommended in mammography guidelines. However, the researchers asserted that the correlation between demographic factors and lack of surveillance was independent of location.

To combat the low rate of screening, there needs to be changes in how mammography is communicated to patients, according to Greenberg.

“I think it's important for health care practitioners to realize that it's not enough to just put information out there. Instead, we have to be more thoughtful about how we implement what we recommend into the actual care process," Greenberg said.