ABSTRACT
PURPOSE: To determine the effect of tomosynthesis imaging as a function of age for breast cancer screening. METHODS: Screening performance metrics from 13 institutions were examined for 12 months prior to introduction of tomosynthesis (period 1) and compared to those after introduction of tomosynthesis (period 2, range 3-22 months). Screening metrics for women ages 40-49, 50-59, 60-69, and 70+ , included rates per 1000 screens for recalls, biopsies, cancers, and invasive cancers detected. RESULTS: Performance parameters were compared for women screened with digital mammography alone (n = 278,908) and digital mammography + tomosynthesis (n = 173,414). Addition of tomosynthesis to digital mammography produced significant reductions in recall rates for all age groups and significant increases in cancer detection rates for women 40-69. Largest recall rate reduction with tomosynthesis was for women 40-49, decreasing from 137 (95% CI 117-156) to 115 (95% CI 95-135); difference, -22 (95% CI -26 to -18; P < .001). Simultaneous increase in invasive cancer detection rate for women 40-49 from 1.6 (95% CI 1.2-1.9) to 2.7 (95% CI 2.2-3.1) with tomosynthesis (difference, 1.1; 95% CI 0.6-1.6; P < .001) was observed. CONCLUSIONS: Addition of tomosynthesis to digital mammography increased invasive cancer detection rates for women 40-69 and decreased recall rates for all age groups with largest performance gains seen in women 40-49. The similar performance seen with tomosynthesis screening for women in their 40s compared to digital mammography for women in their 50s argues strongly for commencement of mammography screening at age 40 using tomosynthesis.
Subject(s)
Breast Neoplasms/diagnostic imaging , Mammography/methods , Radiographic Image Enhancement/methods , Adult , Age Distribution , Age Factors , Aged , Breast Neoplasms/pathology , Early Detection of Cancer , Female , Humans , Mass Screening , Middle Aged , Multimodal Imaging , Sensitivity and SpecificityABSTRACT
IMPORTANCE: Mammography plays a key role in early breast cancer detection. Single-institution studies have shown that adding tomosynthesis to mammography increases cancer detection and reduces false-positive results. OBJECTIVE: To determine if mammography combined with tomosynthesis is associated with better performance of breast screening programs in the United States. DESIGN, SETTING, AND PARTICIPANTS: Retrospective analysis of screening performance metrics from 13 academic and nonacademic breast centers using mixed models adjusting for site as a random effect. EXPOSURES: Period 1: digital mammography screening examinations 1 year before tomosynthesis implementation (start dates ranged from March 2010 to October 2011 through the date of tomosynthesis implementation); period 2: digital mammography plus tomosynthesis examinations from initiation of tomosynthesis screening (March 2011 to October 2012) through December 31, 2012. MAIN OUTCOMES AND MEASURES: Recall rate for additional imaging, cancer detection rate, and positive predictive values for recall and for biopsy. RESULTS: A total of 454,850 examinations (n=281,187 digital mammography; n=173,663 digital mammography + tomosynthesis) were evaluated. With digital mammography, 29,726 patients were recalled and 5056 biopsies resulted in cancer diagnosis in 1207 patients (n=815 invasive; n=392 in situ). With digital mammography + tomosynthesis, 15,541 patients were recalled and 3285 biopsies resulted in cancer diagnosis in 950 patients (n=707 invasive; n=243 in situ). Model-adjusted rates per 1000 screens were as follows: for recall rate, 107 (95% CI, 89-124) with digital mammography vs 91 (95% CI, 73-108) with digital mammography + tomosynthesis; difference, -16 (95% CI, -18 to -14; P < .001); for biopsies, 18.1 (95% CI, 15.4-20.8) with digital mammography vs 19.3 (95% CI, 16.6-22.1) with digital mammography + tomosynthesis; difference, 1.3 (95% CI, 0.4-2.1; P = .004); for cancer detection, 4.2 (95% CI, 3.8-4.7) with digital mammography vs 5.4 (95% CI, 4.9-6.0) with digital mammography + tomosynthesis; difference, 1.2 (95% CI, 0.8-1.6; P < .001); and for invasive cancer detection, 2.9 (95% CI, 2.5-3.2) with digital mammography vs 4.1 (95% CI, 3.7-4.5) with digital mammography + tomosynthesis; difference, 1.2 (95% CI, 0.8-1.6; P < .001). The in situ cancer detection rate was 1.4 (95% CI, 1.2-1.6) per 1000 screens with both methods. Adding tomosynthesis was associated with an increase in the positive predictive value for recall from 4.3% to 6.4% (difference, 2.1%; 95% CI, 1.7%-2.5%; P < .001) and for biopsy from 24.2% to 29.2% (difference, 5.0%; 95% CI, 3.0%-7.0%; P < .001). CONCLUSIONS AND RELEVANCE: Addition of tomosynthesis to digital mammography was associated with a decrease in recall rate and an increase in cancer detection rate. Further studies are needed to assess the relationship to clinical outcomes.
