Vacuum-assisted stereotactic biopsy for isolated BI-RADS 4 microcalcifications: evaluation with histopathology and midterm follow-up results

PURPOSE The aim of this study was to evaluate the 10-gauge vacuum-assisted stereotactic biopsy (VASB) of isolated Breast Imaging Reporting and Data System (BI-RADS) 4 microcalcifications, using histology and follow-up results. METHODS From January 2011 to June 2013, VASB was performed on 132 lesions, and 66 microcalcification-only lesions of BI-RADS 4 were included into our study. VASB was performed using lateral decubitis stereotaxy for all patients. Pathologic results of VASB and further surgical biopsies were reviewed retrospectively. Patients who were diagnosed to have benign lesions by VASB were referred for follow-up. VASB and surgical histopathology results were compared to determine the underestimation ratios. RESULTS Fifteen out of 66 lesions from 63 patients (median age, 47 years; range, 34-88 years) were identified as malignant by VASB. Pathological results after surgery revealed three cases of invasive ductal carcinoma among the 12 VASB-diagnosed ductal carcinoma in situ (DCIS) lesions, for a DCIS underestimation rate of 25%. The atypical ductal hyperplasia underestimation rate was 0% for the three lesions. The follow-up period was at least 10 months, with an average of 22.7 months for all patients and 21.2 months for patients with VASB-diagnosed benign lesions. None of the patients had malignancy during the follow-ups. The false-negative rate was 0% in the follow-up of 48 patients. CONCLUSION VASB should be the standard method of choice for BI-RADS 4 microcalcifications. This method obviates the need for a surgical procedure in 73% of BI-RADS 4 microcalcification-only patients.