Abstract: BACKGROUND ＆ AIM: To evaluate the value of three-dimensional ultrasonography(3D-US) in breast cancer diagnosis. MATERIAL AND METHODS: The LOGIQ 7 sonography imaging system was used to perform conventional two-dimensional and three-dimensional ultrasonographic examinations. The study population consisted of 48 randomized breast cancer patients. RESULTS： The positive rate of the breast cancer in 3D-Us was higher than that of 2D-US,even in the tumor's relation with adjacent tissues and the blood distribution. 3D-US could stereoscopically show the tumor's shape,the relations between the tumor and the skin,chest muscle,chest wall,etc. And it could clearlg show the network of blood vessels of the cancer. CONCLUSION： 3D-US could display breast cancer's structure, adjacent relations and blood vessels because of its high sensitivity. It is helpful for the diagnosis and evaluation of breast cancers.

Key words: breast cancer, three-dimensional ultrasonography (3D-US), three-dimensional color doppler flow imaging (3D-CDFI)