Ultrasonography-guided 14-gauge core biopsy of the breast: Results of 7 years of experience

Purpose: This study assessed the outcomes of ultrasound (US)-guided core needle biopsies (CNBs) of breast lesions with at least 2 years of follow-up to determine the false-negative rate and to evaluate the diagnostic accuracy of CNB. Methods: We retrospectively analyzed 13,254 consecutive US-guided 14-gauge CNBs for breast lesions. We excluded biopsies if non-malignant biopsy result was not confirmed by surgical excision or US-guided vacuum-assisted biopsy, or fewer than 2 years of follow-up data were available. A total of 4,186 biopsies were excluded, and 9,068 breast masses from 7,039 women were included. The pathologic findings from each CNB were assessed using the standard diagnostic reference, defined based on the results of surgical excision, vacuum-assisted biopsy, or at least 2 years of long-term imaging follow-up. The false-negative rate and underestimation rate were calculated. Results: Of the 9,068 CNBs, benign pathology was found in 64.2%, high-risk results in 3.5%, and malignant results in 32.3%. Of the 5,821 benign CNBs, an additional malignancy was found at excision in 63 lesions, leading to a false-negative rate of 2.0% (63 of 3,067). The underestimation rate was 33.6% (111 of 330) for ductal carcinoma in situ and 24.5% (79 of 322) for high-risk results at surgical excision. Most false-negative diagnoses (84.1%, 53 of 63) were recognized through imaging-histology correlations, and immediate rebiopsies were performed. Ten malignancies (15.9%, 10 of 63) had delayed diagnoses and showed progression in follow-up US imaging. Conclusion: US-guided 14-gauge CNB provided optimal diagnostic information. Imaging histology correlations and appropriate imaging follow-up should be performed to avoid delayed diagnoses.