Table 4.
Clinicopathological characteristics after propensity score matching.
| One or Two (n = 6292) | Three or More (n = 1573) | p-Value | |
|---|---|---|---|
| Age, years | 0.966 | ||
| <50 | 4226 (67.2) | 1055 (67.1) | |
| ≥50 | 18,423 (45.3) | 518 (32.9) | |
| Surgery | 1.000 | ||
| Breast-conserving | 2204 (35.0) | 551 (35.0) | |
| Mastectomy | 4088 (65.0) | 1022 (65.0) | |
| Nodal involvement | 1.000 | ||
| No | 4200 (66.8) | 1050 (66.8) | |
| Yes | 2092 (33.2) | 523 (33.2) | |
| Unknown | |||
| Hormonal receptor | 1.000 | ||
| Positive | 1342 (21.3) | 335 (21.3) | |
| Negative | 4950 (78.7) | 1238 (78.7) | |
| HER2 | 0.948 | ||
| Positive | 4072 (64.7) | 1020 (64.8) | |
| Negative | 2220 (35.3) | 553 (35.2) | |
| Tumor type | 0.980 | ||
| IDC | 5858 (93.1) | 1463 (93.0) | |
| ILC | 256 (4.1) | 64 (4.1) | |
| Others | 178 (2.8) | 46 (2.9) |
IDC, invasive ductal carcinoma; ILC, invasive lobular carcinoma.