Purpose: To compare the accuracy of diagnosis of invasive breast cancer with 11- and 8-gauge stereotactic vacuum-assisted biopsy (SVAB) devices and to correlate lesion diameter and accuracy of breast cancer diagnosis at SVAB.
Materials and methods: During a 22-month period, 489 SVAB procedures were performed with an 11-gauge probe and 305 with an 8-gauge probe. SVAB and surgical pathologic results of 104 breast carcinomas were reviewed and correlated with lesion size, number of specimens obtained, and type of SVAB probe used.
Results: Four of 38 ductal carcinoma in situ (DCIS) lesions diagnosed with 11-gauge SVAB demonstrated invasion at surgery, whereas one of 23 DCIS lesions diagnosed with 8-gauge SVAB demonstrated invasion at surgery (P =.6). A mean of 12 specimens per lesion were obtained in each group. In lesions 30 mm or larger, the underestimation rate for DCIS was 43% (three of seven) with 11-gauge SVAB and 17% (one of six) with 8-gauge SVAB (P =.6). Overall, the rate of underestimation for DCIS was significantly higher in lesions 30 mm or larger (four of 13) than in smaller lesions (one of 48, P =.006).
Conclusion: This study demonstrated no difference in breast cancer diagnosis with the 8- and 11-gauge SVAB systems, but the accuracy of breast cancer diagnosis was greater in lesions smaller than 30 mm than in larger lesions.