A Retrospective Study Of Ultrasonographic Characteristics And Clinical Factors Affecting The BI-RADS Classification (Probably Benign Breast Lesions)

Objective: To investigate how many probably benign lesions on US fulfilled the published criteria and to evaluate how clinical and personal factors influenced the categorization of breast lesions.Methods: A total of 487 lesions in 487 women with more than 12 months follow-up after the initial category 3 assessment on US were included. We retrospectively reviewed the initial US images according to previously published criteria, and evaluated several factors that could influence the characterization of breast lesions in clinical practice such as age, multiplicity, palpability, radiologist's experience, and lesion size.Results: Of 487 lesions, 479 (98.36%) were benign and 8 (1.64%) were malignant. Of 487 lesions, 203(41.68%) including 8 malignancies were reassessed as category 4. If strict criteria had been applied at initial US examination, the positive biopsy rate would have been only 3.94% (8/203) and 96.06% (195 of 203) biopsies would have been unnecessary. Lesions in women 40 years or older and multiple lesions were more frequently reassessed as category 4(P = 0.008 and P= 0.006, respectively). The presence of palpability, the radiologist's experience and lesion size did not significantly influence the categorization of breast lesions on US. When strict criteria were adopted in initial classification, of 487 probably benign lesions, 41.68% could be classified as category 4 lesions.Conclusion: The patient's age and the multiplicity of the lesion were found to have a significant influence on the classification of probably benign solid masses.