Recall and biopsy rates reduced with digital mammography

Population-based screening with full-field digital mammography (FFDM) has demonstrated an association with lower recall and biopsy rates than screen film mammography (SFM), intimating that FFDM could reduce the number of diagnostic workups and biopsies that don’t result in breast cancer diagnoses, according to a study published April 1 by Radiology.

Population-based studies in the past that have compared the accuracy of SFM and FFDM have discovered conflicting results with a wide variety of recall rates. Lead author Solveig Hofvind, PhD, of Oslo University College in Norway, and colleagues gathered data from the Norwegian Breast Cancer Screening Program to compare the performance measures and outcomes before, during, and after transitioning from SFM to FFDM.

The researchers included women between the ages of 50 and 69 who underwent mammographic screening every two years. Performance measures were then analyzed to observe the transition between SFM to FFDM, which included the rate of cases, the recall rate, the rate of screen-detected cancer, and the rate of interval cancers.

In total, 1,837,360 Norwegian Breast Cancer Screening Program exams were performed from 1996 to 2010. The average participant age was 58.8 years. Hofvind and colleagues discovered that the overall recall rate was 3.4 percent for SFM and 2.9 percent for FFDM. The biopsy rate for SFM was 1.4 percent and 1.1 percent for FFDM.

After the adoption of FFDM, the positive predictive value of recalled examinations and biopsy procedures increased from 19.3 percent and 48.3 percent to 22.7 percent and 57.5 percent, respectively.

The detection rate of ductal carcinoma in situ was significantly higher with FFDM than SDM, but the detection rate of invasive breast cancer was significantly lower with FFDM. The rates of invasive screening-detected and interval breast cancer maintained stability during the transition to FFDM from SDM.

“We demonstrated that improvements in recall rates and positive predictive values for FFDM are noted beyond the initial transitional phase from SFM to FFDM, and that screening with FFDM is associated with lowering recall and biopsy rates, which are known limitations associated with breast cancer screening,” concluded Hofvind and colleagues.