Change in Indications and Outcomes for Stereotactic Biopsy Following Transition from Full Field Digital Mammography + Digital Breast Tomosynthesis to Full Field Synthetic Mammography + Digital Breast Tomosynthesis.

Abstract

Background: Synthetic 2D mammography was developed to decrease radiation exposure, but to our knowledge there have been no studies evaluating the impact of implementation of full field synthetic mammography/digital breast tomosynthesis (FFSM/DBT) on indications for stereotactic biopsy.

Objective: To compare indications and biopsy outcomes for stereotactic biopsy for full field digital mammography (FFDM/DBT) to those of FFSM/DBT.

Methods: Retrospective chart review of stereotactic biopsies performed from July 2014 to September 2018. Reports were reviewed and indication for biopsy, lesion size, and final pathology were recorded. Comparison between the two groups following transition to FFSM/DBT in 2016 was performed.

Results: 66 of 361 stereotactic biopsies performed in the FFDM/DBT group were malignant (PPV 18.3%), compared to 60 of the 391 biopsies performed in the FFSM/DBT group (PPV 15.4%) with no significant difference in PPV (p = 0.281). There were statistically significant changes in indications for biopsies after transitioning to FFSM/DBT: with a decrease in calcifications referred for biopsy (68.03% vs. 89.75%; p < 0.001), and a statistically significant increase in referral of masses (10.74% vs. 4.43%; p < 0.001), asymmetries (15.60% vs. 5.26%; p < 0.001), and architectural distortion (5.63% vs. 0.55%; p < 0.001). PPV across all indications (21.8% in FFSM/DBT vs. 20.3% in FFDM; p = 0.213), and invasive cancer yield (5.63% vs. 3.32%; p = 0.129) remained comparable following transition to FFSM/DBT without statistically significant differences.

Conclusions: Following transition to FFSM/DBT, statistically significant shifts in indications for biopsies were observed with a decrease in referral of calcifications and an increase for masses, asymmetries and architectural distortions. PPV for stereotactic biopsy was not significantly different and cancer yield across all indications remained similar, with an increase in invasive cancer diagnosis.