Comparison of Conventional 2D CC (Cranio-Caudal) + MLO (Medio-Lateral Oblique) Bi-Directional Photography and 2D-MLO + DBT-MLO (Digital Breast Tomosynthesis) in Mammography Examination

Introduction: Mammography (MMG) is an excellent examination for breast cancer detection and is widely used in both screening and clinical practice. However, the breast thickness and background the concentration of the mammary gland is large among individuals, and the mammary gland and cancer may overlap and it may not be possible to point out a lesion. In recent years, digital breast tomosynthesis (hereinafter referred to as DBT) has been introduced to solve these problems, and its usefulness has been reported in clinical practice. Therefore, in anticipation of a higher cancer detection rate etc., we compared the conventional 2D CC + MLO 2-way MMG examination with 2DMLO + DBTMLO 2-way MMG examination.

Materials and Methods: The combination of 2D CC + MLO and 2DMLO + DBTMLO was read for 95 cases of breast cancer taking 2D CC and MLO and DBT MLO from May 2016 to October 2017. It was judged that the category 3 or more required detailed examination, cancer detection, and cancer detection rates were compared. Subjects were 28 to 87 years of age (median: 55 years), breast composition: high concentration 15.8% (15 cases), heterogeneous high concentration 47.4% (45 cases), mammary gland 28.4% (27 cases), Fatty was 8.4% (8 cases).

Results: The cancer detection rate was 87% for the 2D CC + MLO combination and 94% for the 2DMLO + DBTMLO combination in 95 cases of breast cancer. The interpretation time was 95 minutes for the 2D CC + MLO combination and 110 minutes for the 2DMLO + DBTMLO combination.The breast cancer detected only by the combination of 2D CC + MLO was scattered in 1 case and was classified as Category 3 by FAD. Breast cancer detected only by the combination of 2DMLO + DBTMLO: 8 cases with uneven distribution of breast composition, 3 cases with scattered mammary gland, 3 cases with 5 cases with disordered construction, Category 4 with 3 cases with FAD was.

Conclusion: Both 2D CC + MLO combination and 2DMLO + DBTMLO combination are considered useful for screening MMG examination. In particular, we would like to consider the introduction to medical examinations for the addition of MMG in DBT, but the issue of the amount of image information, the problem of exposure to radiation, the direction of imaging, the establishment of interpretation methods etc. are future issues.

Keywords: Mammography, Breast cancer, Digital Breast Tomosynthesis, Radiology.