Table 1.
Clinicopathological characteristics of estrogen-receptor-negative breast tumors according to basal cytokeratin (CK5/14) status
| Clinicopathological parameter | CK5/14 negative (percentage) | CK5/14 positive (percentage) | p |
| All estrogen-receptor-negative tumors | 60 (63) | 35 (37) | |
| Axillary lymph node status | |||
| Negative | 23 (38) | 19 (54) | 0.14 |
| Positive | 37 (62) | 16 (46) | |
| HER-2 status | |||
| Non-amplified | 35 (58) | 30 (86) | 0.01 |
| Amplified | 18 (30) | 3 (9) | |
| Data missing | 7 (12) | 2 (6) | |
| p63 | |||
| Negative | 57 (95) | 33 (94) | 1.00 |
| Positive | 3 (5) | 2 (6) | |
| p53 | |||
| Negative | 26 (43) | 13 (37) | 0.65 |
| Positive | 26 (43) | 17 (49) | |
| Data missing | 8 (13) | 5 (14) | |
| Histological type | |||
| Invasive ductal or mixed type | 49 (82) | 28 (80) | 0.10 |
| Invasive lobular | 5 (8) | 0 (0) | |
| Medullary or atypical medullary | 5 (8) | 7 (20) | |
| Other types | 1 (2) | 0 (0) |
The p values were calculated, excluding the 'data missing' values, with Fisher's exact test except for the p value of histological type, which was calculated with the χ2 test.