Finding the Best Way to Screen for Breast Cancer

Digital mammography and tomosynthesis combination screening decreased patient recall and increased cancer detection

(RxWiki News) Mammograms are recommended every other year for women older than 50. But this practice draws criticism because the screening emits radiation and can lead to false positives and overdiagnosis.

A new study examined whether combining traditional mammogram with an emerging screening method called tomosynthesis could provide better information to doctors and, in turn, better treatment for patients.

The new research found that combining mammography and tomosynthesis was more effective at finding breast cancer than mammography alone. This combined method also cut down on patients being called back for further screening.

"Talk to your physician about new breast cancer screening options."

Sarah M. Friedewald, MD, section chief of breast imaging and co-medical director of the Caldwell Breast Center at Advocate Lutheran General Hospital in Park Ridge, Illinois, led this research.

Like a mammogram, digital tomography uses X-rays to produce a three-dimensional, rather than two-dimensional, image of the breast.

But while mammograms are widely available, digital tomography is relatively new and has limited availability.

Dr. Friedewald and her colleagues wanted to study whether a combination of mammogram and tomography enhanced the quality of breast cancer screening programs.

The researchers considered breast imaging data collected from 13 sites and including a total of 454,850 examinations — 281,187 digital mammograms and 173,663 screenings combining digital mammography and tomosynthesis.

In the digital mammography group, 29,726 patients were recalled for a second screening and 5,056 biopsies (small tissue samples) gave way to breast cancer diagnosis for 1,207 patients.

The combination screening resulted in 15,541 patients being recalled and 3,285 biopsies yielding cancer diagnosis in 950 patients.

The study found that out of every 1,000 screenings, recall rate was 107 for just mammography and 91 for the combination screening.

For cancer detection, mammograms caught 4.2 cases per 1,000 while the combination screening caught 5.4 cases per 1,000.

Coupling tomosynthesis with mammography showed an increase in positive predictive value (proportion of patients recalled after screening who were diagnosed as having breast cancer) from 4.3 percent to 6.4 percent, according to the study.

Dr. Friedewald and colleagues concluded that combining tomosynthesis with mammography led to a decrease in patient recalls and an increase in breast cancer detection.

This study was published online June 24 in JAMA.

In that same issue, Etta Pisano, MD, vice president for medical affairs, dean of the College of Medicine and professor of radiology at Medical University of South Carolina, wrote in an editorial that Dr. Friedewald and team’s study “adds considerable evidence to how tomosynthesis performs in everyday practice.”

Dr. Pisano added, “Tomosynthesis potentially improves [screening] sensitivity while addressing the two most common arguments against mammography screening — false positive findings and overdiagnosis."

Grant funding for the study was provided by the National Cancer Institute and Hologic, a private medical imaging developer specializing in breast cancer diagnostics.

Several of the study co-authors disclosed having worked as consultants for Hologic, as well as serving on the company’s Scientific Advisory Board. Another study author disclosed a board position for insurer Wellmark Blue Cross/Blue Shield of Iowa and South Dakota.

Review Date: 
June 24, 2014