Objective To investigate the value of retraction phenomenon in coronal plane at threedimensional ultrasonography(3D-US) in preoperative assessment of prognostic factors in breast cancer.Methods Surgical resection specimens of 66 malignant breast lesions in 66 women who had undergone 3D-US were included.The presence of the retraction phenomenon in the coronal plane was evaluated.Pathologic prognostic factors,including tumor size,histologic grade,lymph node status,estrogen receptor (ER) and progesterone receptor (PR) status,and human epidermal growth factor receptor 2 (Cerb-B2) and p53 expression were determined.Correlation of the retraction phenomenon and prognostic factors was analyzed.Results The retraction phenomenon was correlated to the tumor size,histologic grade,and estrogen and progesterone receptor status.Compared with the breast cancer without the retraction phenomenon,the tumor foci with the retraction phenomenon were more likely to show a smaller diameter less than 2 cm (73.7％ vs 46.4％,P ＜0.05),a lower histologic grade with grade Ⅱ (88.2％ vs 42.9％,P ＜0.01),and a higher positive rate of ER and PR (86.8 ％ vs 64.3 ％,P ＜0.05;81.6 ％ vs 57.1％,P ＜0.05).The lymph node status and the expression of the CerB-2 and p53 in the two groups had no significant difference (P ＞0.05).Conclusions The retraction phenomenon in the coronal plane of three-dimensional US may be useful in the noninvasive prediction of prognostic factors of breast cancers.