Digital Breast Tomosynthesis versus Digital Mammography and Overall Survival in a Diagnostic Breast Cancer Cohort with Concurrent Whole-Breast Ultrasound

Abstract Background Digital breast tomosynthesis (DBT) improves lesion conspicuity compared with digital mammography (DM), but whether its use in diagnostic work-up is associated with survival remains uncertain. We evaluated whether diagnostic mammographic modality was associated with overall survival (OS) in women with symptomatic breast cancer undergoing concurrent whole-breast ultrasound. Methods This retrospective cohort included 794 consecutive women diagnosed with breast cancer during evaluation of breast symptoms at a single institution between 2011 and 2015. All underwent diagnostic DM or DBT with same-day bilateral whole-breast ultrasound before biopsy; modality was determined by scheduling and equipment availability. The primary endpoint was 5-year OS. Hazard ratios (HRs) were estimated with Cox regression adjusted for age, breast density, American Joint Committee on Cancer (AJCC) stage, and year of diagnosis. Sensitivity analyses included propensity score matching, restricted mean survival time (RMST), and a stage-stratified model. Results Among 794 women (DM, n = 591; DBT, n = 203), 139 died during a median follow-up of 6.7 years. Five-year OS was 87.1% with DM and 86.2% with DBT. DBT was not significantly associated with OS after adjustment (HR 0.80; 95% CI 0.52–1.23; P = 0.309) or after propensity score matching (HR 0.81; 95% CI 0.53–1.24; P = 0.335). The 5-year RMST difference was − 0.29 months (95% CI − 2.06 to 1.40). No significant modality interaction with breast density or stage was detected. Conclusions In women with symptomatic breast cancer evaluated with concurrent whole-breast ultrasound, DBT showed no significant OS advantage over DM. These findings do not support preferential use of DBT on survival grounds alone.