Role of Breast Tomosynthesis in Diagnosis of Breast Cancer for Japanese Women

Introduction: Mammography is the most basic modality in breast cancer imaging. However, the overlap ofbreast tissue depicted on conventional two-dimensional mammography (2DMMG) may create significant obstaclesto detecting abnormalities, especially in dense or heterogeneously dense breasts. In three-dimensional digital breasttomosynthesis (3DBT), tomographic images of the breast are reconstructed from multiple projections acquired atdifferent angles. It has reported that this technology allows the generation of 3D data, therefore overcoming thelimitations of conventional 2DMMG for Western women. We assessed the detectability of lesions by conventional2DMMG and 3DBT in diagnosis of breast cancer for Japanese women.
Methods: The subjects were 195 breastsof 99 patients (median age of 48 years, range 34~82 years) that had been pathologically diagnosed with breastcancer from December 20, 2010 through March 31, 2011. Both conventional 2DMMG and 3DBT imaging wereperformed for all patients. Detectability of lesions was assessed based on differences in category class.
Results:Of the affected breasts, 77 (75.5%) had lesions assigned to the same categories by 2DMMG and 3DBT. For 24(23.5%) lesions, the category increased in 3DBT indicating improvement in diagnostic performance comparedto 2DMMG. 3DBT improved diagnostic sensitivity for patients with mass, focal asymmetric density (FAD), andarchitectural distortion. However, 3DBT was not statistically superior in diagnosis of the presence or absence ofcalcification.
Conclusions: In this study, 3DBT was superior in diagnosing lesions in form of mass, FAD, and/orarchitectural distortion. 3DBT is a novel technique that may provide a breakthrough in solving the difficultiesof diagnosis caused by parenchyma overlap for Japanese women.