Vacuum-assisted breast biopsy under sonographic guidance : analysis of a 10-year experience

Abstract

PURPOSE: To determine the indications and the diagnostic accuracy of vacuum-assisted breast biopsy (VABB) under ultrasonographic (US) guidance. MATERIALS AND METHODS: This was a retrospective analysis of 2,920 breast lesions in 2,477 consecutive patients who underwent US-guided VABB between February 2002 and December 2011. Indications for US-guided VABB were classified into the following 9 categories: (a) calcifications, (b) complex and intraductal lesions, (c) discordant benign lesions, (d) growing lesions, (e) high-risk lesions, (f) low-suspicion lesions, (g) non-mass lesions, (h) palpable lesions, and (i) patient''s desire to remove the breast lesion. The proportions of each indication for VABB were analyzed as well as the chronological trend of reasons for performing US-guided VABB. The histopathologic diagnoses and malignancy rate of the VABB lesions were analyzed. The pathologic diagnoses made by VABB and the gold standard diagnoses were compared, and the false negative rate, underestimate rate, and agreement rate were assessed. Agreement between pathologic diagnoses obtained by US-guided VABB and the gold standard diagnoses were evaluated with Cohen’s kappa statistic.RESULTS: The proportion of each indication for VABB are as follows: palpable lesions (44.4%), low-suspicion lesions (15.7%), high-risk lesions (12.4%), calcifications (10.3%), patient''s desire to remove the breast lesion (7.4%), complex and intraductal lesions (3.8%), discordant benign lesions (2.7%), non-mass lesions (2.2%), and growing lesions (1.0%). The rate of malignancy in lesions collected by VABB was 5.4%. Calcified lesions showed the highest malignancy rate (36.8%), followed by non-mass lesions (18.5%) and discordant benign lesions (12.7%). The false negative rate was only 0.1%, and the underestimate rate of high-risk lesions and DCIS was 3.1% and 13.8%, respectively, with a 98.7% agreement rate. The agreement between the pathologic diagnoses obtained by US-guided VABB and the gold standard diagnosis was good (κ=0.611, 95% CI: 0.570-0.652). When invasive cancer and DCIS were combined into a malignant group and high-risk and benign lesions were combined into a benign group, the agreement was excellent (κ=0.946, 95% CI: 0.918-0.973). Among 1,512 therapeutic VABB cases, 84.9% showed no residual or recurrent lesions on long-term follow-up US. Complications occurred in 1% of the patients without need for surgical intervention.CONCLUSION: US-guided VABB is an accurate and safe method that can act as an alternative to excisional surgery both in diagnostic and therapeutic circumstances.