Stereotactic biopsy of the breast using a decubitus table: comparison of histologic underestimation rates between 11- and 8-gauge vacuum-assisted breast biopsy

Abstract

Purpose: To evaluate efficacy of the stereotactic vacuum-assisted breast biopsy(SVAB) using a decubitus table and to compare histologic underestimation rate between 11gauge(G)- and 8G-probes.

Materials and methods: Pathologic results of SVAB using a decubitus table of 210(120 with 11G; 90 with 8G)-procedures in 208-women(median age, 48.8 years; range, 27-73 years) were retrospectively reviewed. SVAB was performed for suspicious microcalcification without mass on MMG and US. Surgury was performed for the diagnosis of malignant or high-risk lesion (65(31.0%)). Patients with benign diagnosis (120(57.1%)) underwent MMG follow-up (mean, 340-days). Histologic underestimation was defined as the need to upgrade ADH to DCIS or IDC, and DCIS to IDC at surgery. We analyzed the difference of procedure time, core number and core weight between 11G- and 8G-groups. Statistical significance was determined with chi-square test and 95%-CI for histologic underestimation, and student T-test for comparing two-groups.

Results: Targeting was successful in all 210-biopsies on specimen radiographs. Mean core number, core weight and procedure time were 17.5 (17.5 ± 4.9), 1.57 g (1.57 ± 0.56), 34.5 min (34.5 ± 16.4) with 11G-probe, and 9.6 (9.6 ± 6.2), 1.83g (1.83 ± 0.93), 22.1 min (22.1 ± 12.5) with 8G-probe. Findings in 120 (57.1%) of the biopsies were benign, 36 (17.2%) were high-risk, and 54 (25.7%) were malignant. Two (6.25%) of 32 cases of ADH were upgraded to DCIS in 11G-group, and 2 (9.09%) of 22 in 8G-group. No case of DCIS was upgraded to IDC. There was no increase of complication in 8G-group than 11G-group.

Conclusion: SVAB using a decubitus table is safe and effective method for the evaluation of suspicious microcalcification, and there was no significant difference between 11G- and 8G-probes. But, SVAB with 8G-probe is significantly more time efficient and effective procedure.

Keywords: Add-on unit; Decubitus table; Stereotactic vacuum-assisted breast biopsy.

Figure 1

The case of histologic underestimation on SVAB with an 11-gauge needle. There are clustered coarse heterogeneous calcifications in the right breast which is BIRAD category 4. The pathologic result was mucocele-like lesion with ADH on SVAB, but mucocele-like tumor with DCIS on surgery.

Figure 2

The case of histologic underestimation on SVAB with an 8-gauge needle. There are regional distributed amorphous calcifications in the left breast which is BIRAD category 4. The pathologic result was ADH on SVAB, but DCIS on surgery.