Table 2.
Comparison of different N staging outcomes in occult breast cancer patients.
| Characteristic | N1 (n = 504) (%) | N2 (n = 165) (%) | N3 (n = 174) (%) | χ2 | p |
|---|---|---|---|---|---|
| Age at diagnosis | 0.358 | 0.836 | |||
| <60 | 254 (50.4) | 81 (49.1) | 91 (52.3) | ||
| ≥60 | 250 (49.6) | 84 (50.9) | 83 (47.7) | ||
| ER status | 6.257 | 0.181 | |||
| Negative | 157 (31.2) | 62 (37.6) | 67 (38.5) | ||
| Positive | 291 (57.7) | 90 (54.5) | 95 (54.6) | ||
| Unknown | 56 (11.1) | 13 (7.9) | 12 (6.9) | ||
| PR status | 8.147 | 0.086 | |||
| Negative | 231 (45.8) | 84 (50.9) | 95 (54.6) | ||
| Positive | 203 (40.3) | 64 (38.8) | 67 (38.5) | ||
| Unknown | 70 (13.9) | 17 (10.3) | 12 (6.9) | ||
| HER-2 status | 5.257 | 0.262 | |||
| Negative | 163 (32.3) | 56 (33.9) | 47 (27.0) | ||
| Positive | 53 (10.5) | 21 (12.7) | 28 (16.1) | ||
| Unknown | 288 (57.1) | 88 (53.3) | 99 (56.9) | ||
| Grade | 9.909 | 0.042 | |||
| I–II | 30 (6.0) | 12 (7.3) | 6 (3.4) | ||
| III–IV | 82 (16.3) | 38 (23.0) | 43 (24.7) | ||
| Unknown | 392 (77.8) | 115 (69.7) | 125 (71.8) | ||
| Number of regional LNs examined | 70.243 | <0.001 | |||
| 1–5 | 172 (34.1) | 15 (9.1) | 31 (17.8) | ||
| 6–9 | 63 (12.5) | 29 (17.6) | 5 (2.9) | ||
| ≥10 | 269 (53.4) | 121 (73.3) | 138 (79.3) | ||
| Breast surgery | 4.508 | 0.342 | |||
| Mastectomy | 187 (37.1) | 72 (43.6) | 63 (36.2) | ||
| BCS | 58 (11.5) | 19 (11.5) | 15 (8.6) | ||
| No | 259 (51.4) | 74 (44.8) | 96 (55.2) | ||
| Radiotherapy | 17.914 | <0.001 | |||
| Yes | 242 (48.0) | 104 (63.0) | 109 (62.6) | ||
| No | 262 (52.0) | 61 (37.0) | 65 (37.4) | ||
| Chemotherapy | 7.191 | 0.027 | |||
| Yes | 364 (72.2) | 134 (81.2) | 138 (79.3) | ||
| No | 140 (27.8) | 31 (18.8) | 36 (20.7) |
Abbreviations: ER, estrogen receptor; PR, progesterone receptor; HER-2, human epidermal growth factor receptor-2; BCS, breast-conserving surgery; LN, lymph node.