We report the changes in the findings of imaging examinations (mammography, ultrasonography and contrast-enhanced computed tomography) of three patients with primary breast cancer before and after neoadjuvant chemotherapy, who obtained histologically complete responses after the chemotherapy. The neoadjuvant chemotherapy consisted of four cycles of doxorubicin and docetaxel. All patients were clinically judged as partial responders, because of the remaining tumorous lesions in the imaging examinations. However, these tumorous lesions could be related to the chemotherapy-induced fibrosis and tumor necrosis or the remaining fibrocystic changes. In this study, it was considered very difficult to estimate the extent of residual tumors accurately in patients with primary breast cancer after neoadjuvant chemotherapy by any type of imaging examination.