BI-RADS grade 1 represents a negative result with no abnormal lesions detected, i.e., normal breast gland. The term BI-RADS stands for Breast Imaging Reporting and Data System of the American Radiological Society, and its clinical applications include ultrasound and molybdenum target, etc. The grading can range from 0-6, as follows: I. Grade 0: refers to incomplete assessment. II. Grade 1: Refers to negative results, no abnormal lesions found, i.e. normal breast. III. Grade 2: refers to benign lesions, basically exclude malignancy, regular review is sufficient. Grade 4, 3: basically benign lesions, general lesion malignancy rate is less than 2%, regular review is recommended. V. Grade 4: Suspected malignant lesions, requiring clinical intervention by a physician, usually considering biopsy first. Grade VI.4: can be further categorized into 4a, 4b and 4c. Grade VII.5: malignant possibility ≥95%, aggressive diagnosis and management should be taken. VII.6: Lesions that have been biopsy-proven to be malignant but have not yet been treated.