Table 2.
Procedural variables for all cases of ultrasound-guided diagnostic breast biopsy (8-gauge vacuum-assisted biopsy or spring-loaded 14-gauge core biopsy).
| 8-gauge | 14-gauge | All cases | P-value | |
|---|---|---|---|---|
| Total number of cases | 724 | 719 | 1443 | ----------- |
| Number of cores (all procedures) | <0.001 | |||
| Median (range) | 6.0 (1-38) | 6.0 (2-15) | 6.0 (1-38) | |
| Mean (±SD) | 7.6 (±5.1) | 6.0 (±2.1) | 6.8 (±4.0) | |
| Number of cores (with final pathology as carcinoma) | 0.087 | |||
| Median (range) | 4.0 (2-22) | 6.0 (2-15) | 5.0 (2-22) | |
| Mean (±SD) | 5.5 (±3.6) | 6.0 (±2.2) | 5.9 (±2.6) | |
| Number of cores (with final pathology as benign)# | <0.001 | |||
| Median (range) | 7.0 (1-38) | 6.0 (2-14) | 6.0 (1-38) | |
| Mean (±SD) | 8.2 (±5.4) | 6.0 (±2..0) | 7.4 (±4.6) | |
| Placement of marking microclip* | <0.001 | |||
| Yes | 714 (98.6%) | 428 (59.5%) | 1142 (79.1%) | |
| No | 10 (1.4%) | 291 (40.5%) | 301 (20.9%) |
# For those 8-gauge vacuum-assisted diagnostic biopsies that were done with the intention to attempt 8-gauge vacuum-assisted excision of any given benign breast lesions (n = 354), the median number of cores was 8 (range, 1 to 38) and the mean number of cores was 9.3 (± 5.9).
* Microclip marking was done selectively for ultrasound-guided diagnostic breast biopsy procedures done during the time period from 2001 to 2004, but was generally done more universally in all cases thereafter.