Table 1.
Demographics, Cytology, and Tumor Characteristic of Patients with Negative Axillary Ultrasonography
| Variable | Total (n=1140) | SLN positive (n=144) | SLN negative (n=996) | p Value |
|---|---|---|---|---|
| Age, y, mean, SD | 62 ± 13.2 | 60 ± 12.7 | 62 ± 13.3 | 0.045 |
| Tumor classification, n (%) | 0.060 | |||
| T1 | 817 (71) | 95 (66) | 722 (72) | |
| T2 | 312 (27) | 46 (32) | 266 (27) | |
| Tumor size, mm, mean, SD | 1.7 ± 1.1 | 1.9 ± 1.2 | 1.7 ± 1.1 | |
| Tumor histology, n (%) | 0.575 | |||
| Ductal | 822 (72) | 111 (77) | 711 (71) | |
| Lobular | 120 (11) | 10 (7) | 110 (11) | |
| Ductal and lobular | 110 (10) | 10 (7) | 100 (10) | |
| Other | 10 (4) | 10 (7) | 33 (3) | |
| Tumor grade | 0.239 | |||
| 1 | 315 (28) | 41 (29) | 274 (28) | |
| 2 | 424 (37) | 71 (50) | 377 (38) | |
| 3 | 174 (15) | 29 (21) | 147 (15) | |
| Lymph node status, axillary ultrasound, n (%) | 0.001 | |||
| Negative, no FNA | 924 (81) | 102 (71) | 822 (83) | |
| Suspicious, neg FNA | 216 (19) | 42 (29) | 174 (17) | |
| ER, n (%) | 0.471 | |||
| Positive | 829 (71) | 101 (70) | 728 (73) | |
| Negative | 95 (8) | 16 (11) | 79 (8) | |
| PR, n (%) | 0.662 | |||
| Positive | 719 (63) | 91 (64) | 628 (63) | |
| Negative | 205 (18) | 26 (18) | 179 (18) | |
| Her2, n (%) | <0.0001 | |||
| Positive | 439 (39) | 9 (6) | 430 (43) | |
| Negative | 425 (38) | 127 (88) | 298 (30) | |
| Type of surgery, n (%) | 0.118 | |||
| BCS | 593 (47) | 65 (45) | 528 (53) | |
| Mastectomy | 541 (52) | 79 (55) | 462 (46) | |
| Menopause status, n (%) | <0.0001 | |||
| Postmenopausal | 896 (79) | 98 (68) | 798 (80) | |
| Premenopausal | 239 (21) | 41 (28) | 198 (20) | |
ER, estrogen receptor; Her2, human epidermal growth factor receptor; PR, progesterone receptor; BCS, breast conserving surgery.