- Comparison of clinicopathological features between the young and old patients (≤40 years and >40 years of age) at diagnosis.
| Variables | Group 1 (≤40 years) n (%) | Group 2 (>40 years) n (%) | P-value |
|---|---|---|---|
| Tumor type | 0.174 | ||
| Invasive ductal | 153 (88.5) | 458 (85.6) | |
| Invasive lobular | 2 (1.1) | 33 (6.2) | |
| Ductal carcinoma in situ | 13 (7.5) | 27 (5) | |
| Lobular carcinoma in situ | - | 2 (0.4) | |
| Other | 5 (2.9) | 15 (2.8) | |
| Tumor size | 0.046 | ||
| ≤2 cm | 23 (16.2) | 85 (26.6) | |
| >2 cm - ≤5cm | 80 (56.3) | 162 (50.8) | |
| >5 cm | 39 (27.5) | 72 (22.6) | |
| Histological grading | <0.0001 | ||
| Grade I | 13 (8.6) | 51 (11.2) | |
| Grade II | 55 (36.2) | 242 (53.5) | |
| Grade III | 84 (55.2) | 160 (35.3) | |
| TNM staging | 0.047 | ||
| Stage 0 | 13 (7.7) | 27 (7.2) | |
| Stage I | 58 (34.3) | 166 (44.4) | |
| Stage II | 45 (26.6) | 102 (27.3) | |
| Stage III | 53 (31.4) | 79 (21.1) | |
| Axillary lymph node metastasis | 0.606 | ||
| No | 81 (60.9) | 183 (58.3) | |
| Yes | 52 (39.1) | 131 (41.7) | |
| Number of axillary lymph node metastasis | 0.129 | ||
| 0 | 81 (60.9) | 183 (58.3) | |
| 1-3 | 14 (10.5) | 45 (14.4) | |
| 4-9 | 25 (18.8) | 39 (12.4) | |
| ≥10 | 13 (9.8) | 47 (14.9) | |
| Lymphovascular invasion | <0.0001 | ||
| No | 49 (32.5) | 254 (62.6) | |
| Yes | 102 (67.5) | 152 (37.4) | |
| Distant metastases | <0.0001 | ||
| No | 51 (35.7) | 285 (68.2) | |
| Yes | 92 (64.3) | 133 (31.8) | |
| Locoregional recurrence | 0.163 | ||
| No | 73 (66.4) | 159 (58.7) | |
| Yes | 37 (33.6) | 112 (41.3) | |
| Type of surgery | 0.150 | ||
| Breast conserving surgery | 19 (66.4) | 88 (58.7) | |
| Mastectomy | 117 (33.6) | 366 (41.3) | |
| Estrogen receptor (ER) status | 0.0001 | ||
| Negative | 74 (51.7) | 145 (34.1) | |
| Positive | 69 (48.3) | 280 (65.9) | |
| Progesterone receptor (PR) status | <0.0001 | ||
| Negative | 87 (56.9) | 148 (32.9) | |
| Positive | 66 (43.1) | 301 (67.1) | |
| Her2neu status | 0.002 | ||
| Negative | 84 (55.3) | 294 (69) | |
| Positive | 68 (44.7) | 132 (31) | |
| Tumor subtype | <0.0001 | ||
| Luminal A | 32 (21.5) | 163 (43.1) | |
| Luminal B | 28 (18.8) | 75 (19.8) | |
| Triple negative | 41 (27.5) | 50 (13.2) | |
| HER2-postive | 48 (32.2) | 90 (23.8) | |
| In situ component | 0.441 | ||
| Negative | 87 (61.7) | 163 (57.8) | |
| Positive | 54 (38.3) | 119 (42.2) | |
| Ki67 expression | 0.082 | ||
| Negative | 71 (53.4) | 219 (62) | |
| Positive | 62 (46.6) | 134 (38) | |